Conductive composition and production method thereof, antistatic coating material, antistatic coating, antistatic film, optical filter, and optical information recording medium, and capacitors and production method thereof

ABSTRACT

A conductive composition comprises a π conjugated conductive polymer, a polyanion, and a hydroxy group-containing aromatic compound containing two or more hydroxy groups. An antistatic coating material comprises the conductive composition and a solvent. An antistatic coating is produced by applying the antistatic coating material. A capacitor comprises an anode composed of a porous valve metal body; a dielectric layer formed by oxidizing a surface of the anode; and a cathode formed on the dielectric layer, wherein the cathode has a solid electrolyte layer comprising the conductive composition.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a conductive composition containing a πconjugated conductive polymer and production method thereof. The presentinvention further relates to an antistatic coating material forimparting antistatic properties to a film, an antistatic coatingmaterial having antistatic properties, an antistatic film used inwrapping materials of food and electronic parts, an optical filter usedfor the front surface of a liquid crystal display and a plasma display,and an optical information recording medium, such as CDs and DVDs. Thepresent invention relates to capacitors such as an aluminum electrolyticcapacitor, tantalum electrolytic capacitor, and niobium electrolyticcapacitor and a production method thereof.

The present invention claims priority on Japanese Patent Application No.2004-296380, filed on Oct. 8, 2004, Japanese Patent Application No.2004-337469, filed on Nov. 22, 2004, Japanese Patent Application No.2004-348686, filed on Dec. 1, 2004, Japanese Patent Application No.2005-072757, filed on Mar. 15, 2005, Japanese Patent Application No.2005-072758, filed on Mar. 15, 2005, and Japanese Patent Application No.2005-076972, filed on Mar. 17, 2005, the contents of which areincorporated herein by reference.

2. Description of Related Art

π conjugated conductive polymers are known as organic conductivematerials. The π conjugated conductive polymers is generally referred toan organic polymer composed of the main chain of a conjugated system,and examples of the π conjugated conductive polymers includepolypyrroles, polythiophenes, polyacetylenes, polyphenylenes,polyphenylene vinylenes, polyanilines, polyacenes, polythiophenevinylenes, and copolymers thereof. These π conjugated conductivepolymers are usually synthesized by an electrolytic polymerizationmethod or a chemical oxidative polymerization method.

In the electrolytic polymerization method, a previously prepared basesuch as an electrode material is immersed in a mixed solution of anelectrolyte as a dopant and precursor monomers for constituting a πconjugated conductive polymer to form a film of the π conjugatedconductive polymer on the base. Therefore, mass production is verydifficult.

On the other hand, there are no such limitations on the chemicaloxidative polymerization method. A large amount of a π conjugatedconductive polymer can be produced in a solution by adding oxidant andoxidation polymerization catalysis to precursor monomers of the πconjugated conductive polymer.

However, the π conjugated conductive polymer is obtained as an insolublesolid powder in the chemical oxidative polymerization method because thepolymer becomes less soluble in a solvent as the conjugated system ofthe main chain of the polymer grows. It is difficult to form a uniformfilm of a π conjugated conductive polymer on a base surface if thepolymer is insoluble. Additionally, the π conjugated conductive polymertends to be an amorphous block and then a conductive compositioncontaining the π conjugated conductive polymer has low conductivity.

Therefore, some methods to solubilize the π conjugated conductivepolymers have been attempted. They are a method of introducing afunctional group into the polymers, a method of dispersing the polymersin a binder resin, and a method of adding an anion group-containingpolymeric acid to the polymer.

For example, a method of preparing an aqueous solution ofpoly(3,4-dialkoxythiophene) by the chemical oxidative polymerization of3,4-dialkoxythiophene using oxidant in the presence of polystyrenesulfonic acid, which is an anion group-containing polymeric acid havinga molecular weight of 2000 to 500000, in order to improve thedispersibility in water, is disclosed in Japanese Patent Publication No.2636968. A method of preparing an aqueous colloid solution of a πconjugated conductive polymer by chemical oxidative polymerization of aprecursor monomer of the polymer in the presence of polyacrylic acid, isdisclosed in Japanese Unexamined Patent Application, First PublicationNo. 7-165892.

According to methods disclosed in Japanese Patent Publication No.2636968 and Japanese Unexamined Patent Application, First PublicationNo. 7-165892, an aqueous dispersion solution containing a π conjugatedconductive polymer can be easily prepared. These methods require a πconjugated conductive polymer to contain a large amount of aniongroup-containing polymeric acid for ensuring its dispersibility.Therefore, the problem occurs that the obtained conductive compositionscontain a large amount of compounds which do not contribute toconductivity, making it difficult to achieve high conductivity.

In the chemical oxidative polymerization method, high oxidative oxidantscause unfavorable side reactions in high probability during chemicaloxidative polymerization. Therefore, polymer structures having poorconjugated properties may be produced, the produced polymer may beexcessively oxidized, or impurity ions may remain in the obtainedpolymer, causing low conductivity and long-term stability of theobtained π conjugated conductive polymer. In addition, since the πconjugated conductive polymer is a highly oxidized state, it isconsidered that radicals will be formed by oxidative degradation of aportion of the polymer due to the external environment such as heat, andthen degradation progresses according to a radical chain reaction.

Resin films themselves are insulators and easily electrically charged.Furthermore, resin films tend to charge static electricity by frictionor the like. Moreover, static electricity is not easily removed, butrather accumulates causing various problems.

Particularly, when a resin film is used for food packaging materialemphasizing sanitary properties, dust and dirt are absorbed in display,the appearance is significantly impaired and in some cases the commodityvalue is lowered. When resin film is used for packaging a powder,charged powder is absorbed or repulsed in its packaging or use, andtherefore causes the inconvenience that handling of the powder becomesdifficult. When a precision electronic part is packaged with a resinfilm, it is a feared that the precision electronic part is damaged bythe static electricity; therefore, the occurrence of static electricitymust always be prevented.

Moreover, it is desirable that the surface of an optical filter or anoptical information recording medium has high hardness and hightransparency as well as antistatic properties to prevent the adherenceof dust and dirt due to the static electricity. Particularly, it isdesired that the surface resistance of the antistatic property be in theregion of about 10⁶ to 10¹⁰Ω and that the resistance stabilizes (i.e.,stabilized antistatic properties), from which antistatic coating havingantistatic properties and high hardness is provided on the surface ofoptical filter or optical information recording medium.

In order to impart antistatic properties, for example, a method forcoating a resin film or a surfactant on the surface and a method forkneading a surfactant into a resin forming a resin film or an antistaticcoating have been adopted (for example, see “Fine Chemical AntistaticAgents Latest Market Trend (the first volume),” Vol. 16, No. 15, 1987,p. 24-36, published by CMC).

However, electrostatic prevention based on this surfactant has thedrawback that its conduction mechanism is one of ion conduction,therefore, it is easily affected by humidity, conductivity increases byhigh humidity; however, conductivity decreases by low humidity.Therefore, the antistatic function deteriorates and antistaticperformance is not displayed as necessary in an environment where thehumidity is low, and especially static electricity easily occurs.

If a metal or carbon with electron conduction as conduction mechanism isused, such humidity dependence disappears, but these materials aretotally opaque and not applicable for purposes requiring thetransparency.

Moreover, a metal oxide such as ITO (Indium Tin Oxide) has transparencyand adopts the electron conduction as a conduction mechanism; therefore,it is suited in this respect, but a process using a sputtering apparatusmust used for its film-forming. Not only is the process complicated butalso the manufacturing cost rises. A coating film of inorganic metaloxide has low flexibility. When a film is formed on a thin base film,the coating film may be broken and does not exhibit conductivity. Inaddition, it is feared that peeling occurs at the interface and thetransparency reduces because the adhesion to the base being an organicsubstance is low.

Moreover, π conjugated conductive polymers are known as organicmaterials with electron conduction as the conduction mechanism, but theπ conjugated conductive polymers generally have insoluble and infusibleproperties, and it is difficult to coat the polymers on a base filmafter polymerization. Accordingly, it has been attempted that aniline bepolymerized in the presence of a polymeric acid with a sulfo group(polyanion) to form a water-soluble polyaniline, the obtained mixture isused, coated on a base film and then dried (e.g., see JapaneseUnexamined Patent Application, First Publication No. 1-254764).

However, as with the method described in Japanese Unexamined PatentApplication, First Publication No. 1-254764, if aniline is directlypolymerized on a base, an antistatic coating can be formed. In thiscase, the antistatic coating has low conductivity because the coating isnot obtained by a π conjugated conductive homopolymer, and the adhesionto a resin base is low and manufacturing processes are also complicatedbecause the antistatic coating is water-soluble.

Capacitors are given as example of using the π conjugated conductivepolymers.

In recent years, it has been required to reduce the impedance ofcapacitors used for electronics in a high-frequency region with thedigitalization of electronics. A so-called functional capacitor in whichan oxide film of valve metals such as aluminum, tantalum, and niobium isadopted as a dielectric and a π conjugated conductive polymer is formedon this surface and used as a cathode and thus far has been used inresponse to this requirement.

As shown in Japanese Unexamined Patent Application, First PublicationNo. 2003-37024, it is general that the structure of this functionalcapacitor has an anode consisting of a porous valve metal body, adielectric layer formed by oxidizing the surface of anode, and a cathodeobtained by laminating a solid electrolyte layer, a carbon layer and asilver layer on the dielectric layer. The solid electrolyte layer of thecapacitor is a layer constructed from a π conjugated conductive polymerof pyrrole, thiophene, and the like, and the layer performs to penetrateinto the inside of porous body, come into contact with a larger area ofelectrolyte layer to derive a high capacity, restore defects of thedielectric layer, and prevent leakage of a current.

An electrolytic polymerization method (see Japanese Unexamined PatentApplication, First Publication No. 63-158829) and a chemical oxidativepolymerization method (see Japanese Unexamined Patent Application, FirstPublication No. 63-173313) have been widely known as methods for formingthe ir conjugated conductive polymers.

However, the electrolytic polymerization method has the problem that aconductive layer made of manganese oxide must be formed on the surfaceof the porous valve metal body beforehand, the process is complicated,and further the manganese oxide has low conductivity and weakens theeffect of using the π conjugated conductive polymers having highconductivity.

The chemical oxidative polymerization method has the problem that thepolymerization time is long, the polymerization must be repeated toensure the thickness, the production efficiency of capacitors is low andthe conductivity is also low.

Accordingly, a method wherein conductive polymers are not formed by theelectrolytic polymerization method and the chemical oxidativepolymerization method (see Japanese Unexamined Patent Application, FirstPublication No. 7-105718) has been proposed. A method comprising thesteps of polymerizing aniline while allowing a polymeric acid with asulfo group or carboxy group to coexist to prepare a water-solublepolyaniline, applying the aqueous solution of polyaniline on adielectric layer, and then drying has been described in JapaneseUnexamined Patent Application, First Publication No. 7-105718. Thismethod is simple, but the permeability for the inside of porous body ofthe polyaniline solution deteriorates, the conductivity is low becausethe polymeric acid other than the π conjugated conductive polymer iscontained and the humidity dependence on conductivity by the effect ofpolymeric acid may also be observed.

A capacitor having a low equivalent series resistance (ESR) as index ofimpedance has been desired, and the conductivity of the solidelectrolyte layer must be increased to decrease ESR. As a method forincreasing the conductivity of the solid electrolyte layer, for example,it has been proposed to highly control conditions for the chemicaloxidative polymerization method (see Japanese Unexamined PatentApplication, First Publication No. 11-74157). However, in the productionmethod, the complex chemical oxidative polymerization method is morecomplicated in many cases, thus the simplification and low costing ofprocesses cannot be realized.

SUMMARY OF THE INVENTION

The first object of the present invention is to provide a conductivecomposition excellent in all of electric conductivity, solventsolubility and heat stability and production method thereof.

The second object of the present invention is to provide an antistaticcoating material which can form an antistatic coating having highconductivity, flexibility, and adhesion to base, an antistatic coatingwhich can be prepared by a simple production method of coating, and anantistatic film, an optical filter, and an optical information recordingmedium which all have excellent antistatic property.

Furthermore, the third object of the present invention is to provide acapacitor having excellent conductivity of solid electrolyte layer ofcathode and a low ESR, and a method of producing the capacitor in asimple manner.

A conductive composition of the present invention comprises a πconjugated conductive polymer, a polyanion, and a hydroxygroup-containing aromatic compound containing two or more hydroxygroups.

In the conductive composition of the present invention, the hydroxygroup-containing aromatic compound may be represented by the followingformula (1):

(wherein in formula (1), R represents a group selected from a linear orbranched alkyl group, an alkenyl group, a cycloalkenyl group, an arylgroup, or an aralkyl group, each having 1 to 15 carbon atoms.)

In the conductive composition of the present invention, the hydroxygroup-containing aromatic compound may contain a sulfo group and/or acarboxy group.

The conductive composition according to the present invention mayfurther comprise a dopant.

The conductive composition of the present invention may further comprisea binder resin.

The binder resin may be at least one selected from the group consistingof polyurethane, polyester, acryl resin, polyamide, polyimide, epoxyresin, and polyimide silicone.

A production method of a conductive composition of the present inventioncomprises: a polymerization step for dispersing or dissolving aprecursor monomer, which forms a π conjugated conductive polymer, in asolvent, and polymerizing the precursor monomer in a presence of apolyanion by a chemical oxidative polymerization, and an addition stepfor adding a hydroxy group-containing aromatic compound containing twoor more hydroxy groups.

The production method of the conductive composition of the presentinvention may further comprise a filtration step for partially removingfree ions by an ultrafiltration method.

An antistatic coating material of the present invention comprises: theconductive composition and a solvent.

An antistatic coating of the present invention is produced by applyingthe antistatic coating material.

An antistatic film of the present invention comprises: a film base andthe antistatic coating formed on at least one side of the film base.

An optical filter of the present invention comprises the antistaticcoating.

An optical information recording medium of the present inventioncomprises the antistatic coating.

A capacitor of the present invention comprises: an anode composed of aporous valve metal body; a dielectric layer formed by oxidizing asurface of the anode; and a cathode formed on the dielectric layer,wherein the cathode has a solid electrolyte layer comprising theconductive composition.

In the capacitor, the cathode may further comprise an electrolyte.

A production method of a capacitor of the present invention, comprisesthe steps of: applying a conductive polymer solution, which comprises aπ conjugated conductive polymer, a polyanion, a hydroxy group-containingaromatic compound, and a solvent, to a surface of a dielectric layer ina capacitor intermediate, which comprises an anode composed of a porousvalve metal body and the dielectric layer formed by oxidizing a surfaceof the anode, and drying the conductive polymer solution.

The conductive composition of the present invention is excellent inconductivity and stability.

In the conductive composition of the present invention, if the hydroxygroup-containing aromatic compound contains a sulfo group and/or acarboxy group, the conductivity increased.

If the conductive composition of the present invention further comprisesa binder resin, a film formability and a film strength of a coating tobe formed using the conductive composition are controlled.

According to the production method of the conductive composition of thepresent invention, the conductive composition having excellentconductivity and stability is easily obtained.

If the production method of the conductive composition comprises afiltration step for partially removing free ions by an ultrafiltrationmethod, an operation for converting an anionic acid salt into an anionicacid is easily performed.

By applying the antistatic coating material of the present invention, anantistatic coating is formed having high conductivity, flexibility, andadhesion to a base. Moreover, such an antistatic coating materialproduces the antistatic coating at a low cost because a sufficientantistatic property is obtained by using it in a small amount.

In the antistatic coating material of the present invention, if thehydroxy group-containing aromatic compound contains a sulfo group and/ora carboxy group, the conductivity of the antistatic coating furtherincreases.

If the antistatic coating material of the present invention furthercomprises a dopant, the conductivity of the antistatic coating furtherincreases and heat resistance is improved.

If a binder resin is contained in the antistatic coating material,adhesion to a base is improved.

If the binder resin is at least one selected from the group consistingof: polyurethane, polyester, acryl resin, polyamide, polyimide, epoxyresin, polyimide silicone, and melamine resin, the binder resin iseasily mixed with essential components of the antistatic material.

The antistatic coating is excellent in conductivity, flexibility, andadhesion to a base, and can be produced by a simple production method,that is, coating.

The antistatic film, optical filter, and optical information recordingmedium are excellent in antistatic properties, and prevent theoccurrence of static electricity.

The capacitor of the present invention has a low equivalent seriesresistance because the conductivity of cathode is high.

In the capacitor of the present invention, if an electrolyte iscontained in the cathode, the rate of deriving an electrostatic capacityincreases.

The production method of the capacitor of the present invention enablesto simply produce the capacitor having a high conductivity of cathodeand a low equivalent series resistance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an embodiment of the opticalfilter according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the opticalinformation recording medium according to the present invention.

FIG. 3 is a cross-sectional view showing an embodiment of the capacitoraccording to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

A conductive composition according to the present invention is explainedbelow.

The conductive composition of the present invention comprises a πconjugated conductive polymer, a polyanion, and a hydroxygroup-containing aromatic compound containing two or more hydroxygroups.

Each component of the conductive composition is explained as follows.

(π Conjugated Conductive Polymer)

The π conjugated conductive polymers can be used if they are organicpolymers in which the main chain is constructed by a π-conjugate system.Examples of the polymer include polypyrroles, polythiophenes,polyacetylenes, polyphenylenes, polyphenylene vinylenes, polyanilines,polyacenes, polythiophene vinylenes, and copolymers thereof.Polypyrroles, polythiophenes, and polyanilines are preferable from inview of ease of polymerization and stability in the air.

The π conjugated conductive polymers can be obtained sufficientconductivity and compatibility for binder resins as they areunsubstituted, but it is preferable that functional groups such asalkyl, carboxyl, sulfo, alkoxy, hydroxyl, and cyano groups areintroduced into the π conjugated conductive polymers to increase theconductivity and dispersibility or solubility for binder resins.

Examples of the π conjugated conductive polymer specifically includepolypyrrole, poly(3-methylpyrrole), poly(N-methylpyrrole),poly(3-ethylpyrrole), poly(3-n-propylpyrrole), poly(3-butylpyrrole),poly(3-octylpyrrole), poly(3-decylpyrrole), poly(3-dodecylpyrrole),poly(3,4-dimethylpyrrole), poly(3,4-dibutylpyrrole),poly(3-carboxypyrrole), poly(3-methyl-4-carboxypyrrole),poly(3-methyl-4-carboxyethylpyrrole),poly(3-methyl-4-carboxybutylpyrrole), poly(3-hydroxypyrrole),poly(3-methoxypyrrole), poly(3-ethoxypyrrole), poly(3-butoxypyrrole),poly(3-hexyloxypyrrole), poly(3-methyl-4-hexyloxypyrrole),polythiophene, poly(3-methylthiophene), poly(3-ethylthiophene),poly(3-propylthiophene), poly(3-butylthiophene), poly(3-hexylthiophene),poly(3-heptylthiophene), poly(3-octylthiophene), poly(3-decylthiophene),poly(3-dodecylthiophene), poly(3-octadecylthiophene),poly(3-bromothiophene), poly(3-chlorothiophene), poly(3-iodothiophene),poly(3-cyanothiophene), poly(3-phenylthiophene),poly(3,4-dimethylthiophene), poly(3,4-dibutylthiophene),poly(3-hydroxythiophene), poly(3-methoxythiophene),poly(3-ethoxythiophene), poly(3-butoxythiophene),poly(3-hexyloxythiophene), poly(3-heptyloxythiophene),poly(3-octyloxythiophene), poly(3-decyloxythiophene),poly(3-dodecyloxythiophene), poly(3-octadecyloxythiophene),poly(3,4-dihydroxythiophene), poly(3,4-dimethoxythiophene),poly(3,4-diethoxythiophene), poly(3,4-dipropoxythiophene),poly(3,4-dibutoxythiophene), poly(3,4-dihexyloxythiophene),poly(3,4-diheptyloxythiophene), poly(3,4-dioctyloxythiophene),poly(3,4-didecyloxythiophene), poly(3,4-didodecyloxythiophene),poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene),poly(3,4-butenedioxythiophene), poly(3-methyl-4-methoxythiophene),poly(3-methyl-4-ethoxythiophene), poly(3-carboxythiophene),poly(3-methyl-4-carboxythiophene),poly(3-methyl-4-carboxyethylthiophene),poly(3-methyl-4-carboxybutylthiophene), polyaniline,poly(2-methylaniline), poly(3-isobutylaniline), poly(2-anilinesulfonicacid), poly(3-anilinesulfonic acid), and the like.

Among these polymers, a (co)polymer composed of one or two compoundsselected from polypyrrole, polythiophene, poly(N-methylpyrrol),poly(3-methylthiophene), poly(3,4-ethylenedioxythiophene) is suitablyused in view of resistance value and reactivity. Polypyrrole andpoly(3,4-ethylenedioxythiophene) are more preferable in view ofincreasing the conductivity and improving the heat resistance.

Moreover, alkyl-substituted compounds such as poly(N-methylpyrrol) andpoly(3-methylthiophene) are more preferable because the solventsolubility, compatibility for binder resins, and dispersibility areimproved. In the alkyl groups, methyl group is preferable because itdoes not exert an adverse effect on the conductivity. Furthermore,poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate(abbreviated as PEDOT-PSS) is preferable in that the transparency afterforming the coating film becomes favorable because it has higher heatstability and low degree of polymerization.

The above π conjugated conductive polymers can be easily produced bychemical oxidative polymerization of precursor monomers forming πconjugated conductive polymers in the presence of an appropriateoxidant, an oxidation catalyst, and a polyanion dopant described later.

(Precursor Monomers)

A precursor monomer has a π-conjugate system in a molecule and forms theπ-conjugate system in the main chain when it is polymerized by thefunction of an appropriate oxidant. Examples of the precursor monomersinclude pyrroles and their derivatives, thiophenes and theirderivatives, anilines and their derivatives, and the like.

Specific examples of the precursor monomers include pyrrole,3-methylpyrrole, 3-ethylpyrrole, 3-n-propylpyrrole, 3-butylpyrrole,3-octylpyrrole, 3-decylpyrrole, 3-dodecylpyrrole, 3,4-dimethylpyrrole,3,4-dibutylpyrrole, 3-carboxypyrrole, 3-methyl-4-carboxypyrrole,3-methyl-4-carboxyethylpyrrole, 3-methyl-4-carboxybutylpyrrole,3-hydroxypyrrole, 3-methoxypyrrole, 3-ethoxypyrrole, 3-butoxypyrrole,3-hexyloxypyrrole, 3-methyl-4-hexyloxypyrrole, N-methylpyrrole,thiophene, 3-methyl-thiophene, 3-ethylthiophene, 3-propylthiophene,3-butylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3-octylthiophene,3-decylthiophene, 3-dodecylthiophene, 3-octadecylthiophene,3-bromothiophene, 3-chlorothiophene, 3-iodothiophene, 3-cyanothiophene,3-phenylthiophene, 3,4-dimethylthiophene, 3,4-dibutylthiophene,3-hydroxythiophene, 3-methoxythiophene, 3-ethoxythiophene,3-butoxythiophene, 3-hexyloxythiophene, 3-heptyloxythiophene,3-octyloxythiophene, 3-decyloxythiophene, 3-dodecyloxythiophene,3-octadecyloxythiophene, 3,4-dihydroxythiophene, 3,4-dimethoxythiophene,3,4-diethoxythiophene, 3,4-dipropoxythiophene, 3,4-dibutoxythiophene,3,4-dihexyloxythiophene, 3,4-diheptyloxythiophene,3,4-dioctyloxythiophene, 3,4-didecyloxythiophene,3,4-didodecyloxythiophene, 3,4-ethylenedioxythiophene,3,4-propylenedioxythiophene, 3,4-butenedioxythiophene,3-methyl-4-methoxythiophene, 3-methyl-4-ethoxythiophene,3-carboxythiophene, 3-methyl-4-carboxythiphene,3-methyl-4-carboxyethylthiphene, 3-methyl-4-carboxybutylthiphene,aniline, 2-methylaniline, 3-isobutylaniline, 2-anilinesulfonic acid,3-anilinesulfonic acid, and the like.

(Solvents)

As solvents used in the preparation of the π conjugated conductivepolymers, they are not specially limited and may be solvents which areable to dissolve or disperse the precursor monomers and keep theoxidizing power of oxidants and oxidation catalysts. For example, polarsolvents such as water, N-methyl-2-pyrrolidone, N,N-dimethylformamide,N,N-dimethylacetamide, dimethylsulfoxide, hexamethylenephosphortriamide, acetonitrile, benzonitrile, hexamethylphosphorictriamide, 1,3-dimethyl-2-imidazolidine, dimethylimidazoline, ethylacetate, sulforan, diphenyl sulfone, and the like; phenols such ascresol, phenol, xylenol, and the like; alcohols such as methanol,ethanol, propanol, butanol, and the like; ketones such as acetone,methyl ethyl ketone, hydrocarbons such as hexane, benzene, toluene, andthe like; carboxylic acids such as formic acid, acetic acid, and thelike; carbonate compounds such as ethylene carbonate, propylenecarbonate, and the like; ether compounds such as dioxane, diethyl ether,and the like; chain ethers such as ethylene glycol dialkyl ethers,propylene glycol dialkyl ethers, and the like; heterocyclic compoundssuch as 3-methyl-2-oxazolidinone, nitrile compounds such asacetonitrile, glutarodinitrile, methoxyacetonitrile, propionitrile,benzonitrile, and the like are given. These solvents may be usedindividually, as mixtures of two or more of them, or as mixtures withother organic solvents.

(Oxidants and Oxidation Catalysts)

Oxidants and oxidation catalysts may be ones which are able to oxidizethe precursor monomers to obtain the π conjugated conductive polymers.Examples of them include peroxodisulfates such as ammoniumperoxodisulfate, sodium peroxodisulfate, potassium peroxodisulfate, andthe like; transition metal compounds such as ferric chloride, ferricsulfate, ferric nitrate, cupric chloride, and the like; metal halidecompounds such as boron trifluoride, aluminum chloride, and the like;metal oxides such as silver oxide, cesium oxide, and the like; peroxidessuch as hydrogen peroxide, ozone, and the like; organic peroxides suchas benzoyl peroxide, and the like; oxygen, and the like.

(Polyanion)

Polyanions are substituted or unsubstituted polyalkylenes, substitutedor unsubstituted polyalkylenes, substituted or unsubstituted polyimides,substituted or unsubstituted polyamides, substituted or unsubstitutedpolyesters, and copolymers thereof, and are composed of structure unitshaving anion groups and structure units having no anion groups.

Anion groups of polyanion function as a dopant for the π conjugatedconductive polymer and improve conductivity and heat resistance of the πconjugated conductive polymer.

Polyalkylenes are polymers in which the main chain is constructed byrepeated methylenes. Examples of polyalkylenes include polyethylene,polypropylene, polybutene, polypentene, polyhexene, polyvinyl alcohol,polyvinyl phenol, poly3,3,3-trifluoropropylene, polyacrylonitrile,polyacrylate, polystyrene, and the like.

Polyalkenylenes are polymers composed of structural units in which oneor more unsaturated bonds (vinyl groups) are contained in the mainchain. Specific examples of polyalkenylenes include polymers comprisingone or more structural units selected from propenylene,1-methylpropenylene, 1-butylpropenylene, 1-decylpropenylene,1-cyanopropenylene, 1-phenylpropenylene, 1-hydroxypropenylene,1-butenylene, 1-methyl-1-butenylene, 1-ethyl-1-butenylene,1-octyl-1-butenylene, 1-pentadecyl-1-butenylene, 2-methyl-1-butenylene,2-ethyl-1-butenylene, 2-butyl-1-butenylene, 2-hexyl-1-butenylene,2-octyl-1-butenylene, 2-decyl-1-butenylene, 2-dodecyl-1-butenylene,2-phenyl-1-butenylene, 2-butenylene, 1-methyl-2-butenylene,1-ethyl-2-butenylene, 1-octyl-2-butenylene, 1-pentadecyl-2-butenylene,2-methyl-2-butenylene, 2-ethyl-2-butenylene, 2-butyl-2-butenylene,2-hexyl-2-butenylene, 2-octyl-2-butenylene, 2-decyl-2-butenylene,2-dodecyl-2-butenylene, 2-phenyl-2-butenylene,2-propylene-phenyl-2-butenylene, 3-methyl-2-butenylene,3-ethyl-2-butenylene, 3-butyl-2-butenylene, 3-hexyl-2-butenylene,3-octyl-2-butenylene, 3-decyl-2-butenylene, 3-dodecyl-2-butenylene,3-phenyl-2-butenylene, 3-propylene-phenyl-2-butenylene, 2-pentenylene,4-propyl-2-pentenylene, 4-butyl-2-pentenylene, 4-hexyl-2-pentenylene,4-cyano-2-pentenylene, 3-methyl-2-pentenylene, 4-ethyl-2-pentenylene,3-phenyl-2-pentenylene, 4-hydroxy-2-pentenylene, hexenylene, and thelike.

In these polymers, substituted or unsubstituted butenylens arepreferable from the fact that an interaction between an unsaturated bondand a π conjugated conductive polymer exists and substituted orunsubstituted butadienes are easily synthesized as starting materials.

Examples of polyimides include polyimides from anhydrides such aspyromellitic dianhydride, biphenyltetracarboxylic dianhydride,benzophenone tetracarboxylic dianhydride, 2,2,3,3-tetracarboxyphenylether dianhydride, and 2,2-[4,4′-di(dicarboxyphenyloxy)phenyl]propanedianhydride; and diamines such as oxydiamine, p-phenylenediamine,m-phenylenediamine, and benzophenonediamine.

Examples of polyamides include polyamide 6, polyamide 6, 6, polyamide 6,10, and the like.

Examples of polyesters include polyethylene terephthalate, polybutyleneterephthalate, and the like.

When polyanions have substituents, examples of substituents includealkyl, hydroxyl, amino, carboxyl, cyano, phenyl, phenol, ester, alkoxygroups, and the like. If solubility for solvents, heat resistance, andcompatibility with resins are considered, alkyl, hydroxyl, phenol, andester groups are preferable.

Alkyl groups can increase solubility for and dispersibility in polarsolvents or nonpolar solvents, and compatibility with and dispersibilityin resins. Hydroxyl groups can easily form a hydrogen bond with anotherhydrogen atom and increase solubility for organic solvents andcompatibility with, dispersibility for, and adhesion to resins.Moreover, cyano and hydroxyphenyl groups can increase compatibility withand solubility for polar resins and also increase heat resistance.

In the above substituents, alkyl, hydroxyl, ester, and cyano groups arepreferable.

Examples of the alkyl groups include chain alkyl groups such as methyl,ethyl, propyl, butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, decyl,and dodecyl groups; and cycloalkyl groups such as cyclopropyl,cyclopentyl, and cyclohexyl groups. If solubility for solvents,dispersibility in resins, steric hindrance, and the like are considered,C₁ to C₁₂ alkyl groups are more preferable.

Examples of the hydroxyl groups include hydroxyl groups directly bondedto the main chain of polyanions or hydroxyl groups bonded to the mainchain via other functional groups. Examples of the other functionalgroups include C₁ to C₇ alkyl groups, C₂ to C₇ alkenyl groups, amidegroups, imide groups, and the like. The hydroxyl groups are substitutedat the end or in these functional groups. In these groups, hydroxylgroups bonded at the end of C₁ to C₆ alkyl groups are more preferable inview of compatibility with resins and solubility for organic solvents.

Examples of the amino groups include amino groups directly bonded to themain chain of polyanions or amino group bonded to the main chain viaother functional groups. Examples of the other functional groups includeC₁ to C₇ alkyl groups, C₂ to C₇ alkenyl groups, amide groups, imidegroups, and the like. The amino groups are substituted at the end or inthese functional groups.

Examples of the phenol groups, phenol groups directly bonded to the mainchain of polyanions or phenol group bonded to the main chain via otherfunctional groups. Examples of the other functional groups include C₁ toC₇ alkyl groups, C₂ to C₇ alkenyl groups, amide groups, imide groups,and the like. The phenol groups are substituted at the end or in thesefunctional groups.

Examples of the ester groups include alkyl ester groups or aromaticester groups directly bonded to the main chain of polyanions or alkylester groups or aromatic ester groups bonded to the main chain via otherfunctional groups.

Examples of the cyano groups include cyano groups directly bonded to themain chain of polyanions or cyano groups bonded to the end of C₁ to C₇alkyl groups bonded to the main chain, cyano groups bonded the end of C₂to C₇ alkenyl groups to the main chain, and the like.

Any anion group among polyanions can be used if the anion group can bedoped with the π conjugated conductive polymer by chemical oxidation,and preferred examples include a mono-substituted sulfuric acid estergroup, mono-substituted phosphoric acid ester group, phosphoric group,carboxy group, and sulfo groups in view of easy production andstability. Furthermore, a sulfo group, mono-substituted phosphoric acidester group, carboxy group, and the like are more preferable in view ofthe doping effect of the functional groups to the π conjugatedconductive polymers.

Preferred anion groups are provided in the main chain of polyanionsadjacently or at a constant interval.

Specific examples of polyanions include polyvinyl sulfonic acid,polystyrene sulfonic acid, polyallyl sulfonic acid, polyethyl acrylatesulfonic acid, polybutyl acrylate sulfonic acid, polyacryl sulfonicacid, polymethacryl sulfonic acid, poly-2-acrylamide-2-methylpropanesulfonic acid, polyisoprene sulfonic acid, polyvinyl carboxylic acid,polystyrene carboxylic acid, polyallyl carboxylic acid, polyacrylcarboxylic acid, polymethacryl carboxylic acid,poly-2-acrylamide-2-methylpropane carboxylic acid, polyisoprenecarboxylic acid, polyacrylic acid, and the like.

These polyanions may be homopolymers or copolymers of two or more ofthem.

Among these polyanions, polystyrene sulfonic acid, polyisoprene sulfonicacid, polyethyl acrylate sulfonic acid, polybutyl acrylate sulfonic acidare preferable from effects of increasing compatibility with binderresins, further increasing conductivity of resultant antistatic coatingmaterial, and suppressing thermal decomposition of the π conjugatedconductive polymers.

Examples of production methods of polyanions include a method wherein ananion group is directly introduced into a polymer free of an anion groupwith an acid, a method wherein a polymer free of an anion group issulfonated with a sulfonating agent, and a method wherein a polymer isproduced by polymerization of an anion group containing polymerizablemonomer.

As the method wherein a polymer is produced by polymerization of ananion group containing polymerizable monomer, a method wherein an aniongroup containing polymerizable monomer is produced by oxidativepolymerization or radical polymerization in a solvent in the presence ofan oxidant and/or a polymerization catalyst. Specifically, apredetermined amount of an anion group containing polymerizable monomeris dissolved in a solvent, kept to a certain temperature, a solutionobtained by dissolving predetermined amounts of an oxidant and/or apolymerization catalyst in a solvent beforehand is added thereto andthen the mixture is reacted for a predetermined time. A polymer obtainedby this reaction is adjusted to a certain concentration with a solvent.In this preparation method, a polymerizable monomer free of an aniongroup may also be copolymerized with an anion group containingpolymerizable monomer.

The oxidants, oxidation catalysts, and solvents to be used in thepolymerization of an anion group containing polymerizable monomers aresame as those used in the polymerization of precursor monomers formingthe π conjugated conductive polymers.

When the obtained polymers are polyanion salts, they are preferablymodified into polyanionic acids. As methods for modifying the polymersinto polyanionic acids, ion-exchange method using an ion-exchange resin,dialysis method, ultrafiltration method, and the like are given, and theultrafiltration method is preferable in view of easy operation.

A part of the anion group containing polymerizable monomers issubstituted by a mono-substituted sulfate group, a carboxyl group, sulfogroup, and the like. Examples of anion group containing polymerizablemonomers include a substituted or unsubstituted ethylenesulfonic acidcompound, a substituted or unsubstituted styrene sulfonic acid compound,a substituted or unsubstituted acrylate sulfonic acid compound, asubstituted or unsubstituted methacrylate sulfonic acid compound, asubstituted or unsubstituted acrylamide sulfonic acid compound, asubstituted or unsubstituted cyclovinylene sulfonic acid compound, asubstituted or unsubstituted butadiene sulfonic acid compound, and asubstituted or unsubstituted vinyl aromatic sulfonic acid compound.

Specific examples include vinyl sulfonic acid and salts thereof, allylsulfonic acid and salts thereof, methallylsulfonic acid and saltsthereof, styrene sulfonic acid, methallyloxy benzene sulfonic acid andsalts thereof, allyloxy benzene sulfonic acid and salts thereof,α-methylstyrenesulfonic acid and salts thereof, acrylamide-t-butylsulfonic acid and salts thereof, 2-acrylamide-2-methylpropane sulfonicacid and salts thereof, 2-acrylamide-2-methylpropane sulfonic acid andsalts thereof, cyclobutene-3-sulfonic acid and salts thereof, isoprenesulfonic acid and salts thereof, 1,3-butadiene-1-sulfonic acid and saltsthereof, 1-methyl-1,3-butadiene-2-sulfonic acid and salts thereof,1-methyl-1,3-butadiene-4-sulfonic acid and salts thereof, ethyl acrylatesulfonic acid (CH₂CH—COO—(CH₂)₂—SO₃H) and salts thereof, propyl acrylatesulfonic acid (CH₂CH—COO—(CH₂)₃—SO₃H) and salts thereof, t-butylacrylate sulfonic acid (CH₂CH—COO—C(CH₃)₂—SO₃H) and salts thereof,n-butyl acrylate sulfonic acid (CH₂CH—COO—(CH₂)₄—SO₃H) and saltsthereof, ethyl vinylacetate sulfonic acid (CH₂CHCH₂—COO—(CH₂)₂—SO₃H) andsalts thereof, t-butyl vinylacetate sulfonic acid(CH₂CH(CH₂)₂—COO—C(CH₃)₂CH₂—SO₃H) and salts thereof, ethyl 4-pentenoatesulfonic acid (CH₂CH(CH₂)₂—COO—(CH₂)₂—SO₃H) and salts thereof, propyl4-pentenoate sulfonic acid (CH₂CH(CH₂)₂—COO—(CH₂)₃—SO₃H) and saltsthereof, n-butyl 4-pentenoate sulfonic acid(CH₂CH—(CH₂)₂—COO—(CH₂)₄—SO₃H) and salts thereof, t-butyl 4-pentenoatesulfonic acid (CH₂CH(CH₂)₂—COO—C(CH₃)₂—CH₂—SO₃H) and salts thereof,phenylene 4-pentenoate sulfonic acid (CH₂CH(CH₂)₂—COO—C₆H₄—SO₃H) andsalts thereof, naphthalene 4-pentenoate sulfonic acid(CH₂CH(CH₂)₂—COO—C₁₀H₈—SO₃H) and salts thereof, ethyl methacrylatesulfonic acid (CH₂C(CH₃)—COO—(CH₂)₂—SO₃H) and salts thereof, propylmethacrylate sulfonic acid (CH₂C(CH₃)—COO—(CH₂)₃—SO₃H) and saltsthereof, t-butyl methacrylate sulfonic acid(CH₂C(CH₃)—COO—C(CH₃)₂CH₂—SO₃H) and salts thereof, n-butyl methacrylatesulfonic acid (CH₂C(CH₃)—COO—(CH)₄—SO₃H) and salts thereof, phenylenemethacrylate sulfonic acid (CH₂C(CH₃)—COO—C₆H₄—SO₃H) and salts thereof,naphthalene methacrylate sulfonic acid (CH₂C(CH₃)—COO—C₁₀H₈—SO₃H) andsalts thereof, polyvinyl carboxylic acid, polystyrene carboxylic acid,polyallyl carboxylic acid, polyacryl carboxylic acid, polymethacrylcarboxylic acid, poly-2-acrylamide-2-methylpropanecarboxylic acid,polyisoprene carboxylic acid, polyacrylic acid, and the like. Thepolyanions may also be copolymers containing two or more of them.

Examples of polymerizable monomers free of an anion group includeethylene, propene, 1-butene, 2-butene, 1-pentene, 2-pentene, 1-hexene,2-hexene, styrene, p-methylstyrene, p-ethylstyrene, p-butylstyrene,2,4,6-trimethylstyrene, p-methoxystyrene, α-methylstyrene,2-vinylnaphthalene, 6-methyl-2-vinylnaphthalene, 1-vinylimidazole,vinylpyridine, vinyl acetate, acrylaldehyde, acrylonitrile,N-vinyl-2-pyrrolidone, N-vinylacetamide, N-vinylformamide,N-vinylimidazole, acrylamide, N,N-dimethylacrylamide, acrylic acid,methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate,i-butyl acrylate, t-butyl acrylate, i-octyl acrylate, i-nonylbutylacrylate, lauryl acrylate, allyl acrylate, stearyl acrylate, i-bonylacrylate, cyclohexyl acrylate, benzyl acrylate, ethylcarbitol acrylate,phenoxyethyl acrylate, hydroxyethyl acrylate, methoxyethyl acrylate,ethoxyethyl acrylate, methoxybutyl acrylate, methacrylic acid, methylmethacrylate, ethyl methacrylate, n-butyl methacrylate, i-butylmethacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, laurylmethacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexylmethacrylate, benzyl methacrylate, 2-hydroxyethyl methacrylate,2-hydroxypropyl methacrylate, acryloylmorpholine, vinylamine,N,N-dimethylvinylamine, N,N-diethylvinylamine, N,N-dibutylvinylamine,N,N-di-t-butylvinylamine, N,N-diphenylvinylamine, N-vinylcarbazole,vinyl alcohol, vinyl chloride, vinyl fluoride, methyl vinyl ether, ethylvinyl ether, cyclopropene, cyclobutene, cyclopentene, cyclohexene,cycloheptene, cyclooctene, 2-methylcyclohexene, vinylphenol,1,3-butadiene, 1-methyl-1,3-butadiene, 2-methyl-1,3-butadiene,1,4-dimethyl-1,3-butadiene, 1,2-dimethyl-1,3-butadiene,1,3-dimethyl-1,3-butadiene, 1-octyl-1,3-butadiene,2-octyl-1,3-butadiene, 1-phenyl-1,3-butadiene, 2-phenyl-1,3-butadiene,1-hydroxy-1,3-butadiene, 2-hydroxy-1,3-butadiene, and the like.

As a polyanion, a polyisoprene sulfonic acid, a copolymer containing apolyisoprene sulfonic acid, a polymethallyl sulfonic acid, a copolymercontaining a polymethallyl sulfonic acid, a polysulfoethyl methacrylate,a copolymer containing a polysulfoethyl methacrylate, apoly(4-sulfobutyl methacrylate), a copolymer containing apoly(4-sulfobutyl methacrylate), a polymethallyloxybenzene sulfonicacid, a copolymer containing a polymethallyloxybenzene sulfonic acid, apolystyrene sulfonic acid, a copolymer containing a polystyrene sulfonicacid, and the like are preferred in view of solubility in a solvent andconductivity.

The solvent solubility and compatibility with binder resins can becontrolled by copolymerizing these polymerizable monomers free of ananion group.

The degree of polymerization of polyanions is preferably in a range of10 to 10000 monomer units, more preferably in a range of 50 to 10000monomer units in view of solubility in a solvent and conductivity.

The content of polyanions contained in the conductive composition, theantistatic coating material, or the solid electrolyte layer of thecapacitor is preferably 0.1 to 10 mol, and more preferably 1 to 7 mol to1 mol of the π conjugated conductive polymer. If the content ofpolyanions is less than 0.1 mol, the doping effect on the π conjugatedconductive polymer tends to weaken, and conductivity may beinsufficient. In addition, the dispersibility and solubility in thesolvent are deteriorated making it difficult to obtain uniformdispersions. If the content of polyanions is more than 10 mol, thecontent of the π conjugated conductive polymer in the conductivecomposition decreases making it difficult to obtain sufficientconductivity.

(Hydroxy Group-Containing Aromatic Compound)

A hydroxy group-containing aromatic compound is composed of an aromaticring to which two or more hydroxy groups are bonded. The hydroxygroup-containing aromatic compound has a strong interaction between thehydroxy groups and the aromatic ring, and tends to release hydrogen fromthe compound.

Examples of hydroxy group-containing aromatic compounds include1,4-dihydroxybenzene, 1,3-dihydroxybenzene,2,3-dihydroxy-1-pentadecylbenzene, 2,4-dihydroxyacetophenone,2,5-dihydroxyacetophenone, 2,4-dihydroxybenzophenone,2,6-dihydroxybenzophenone, 3,4-dihydroxybenzophenone,3,5-dihydroxybenzophenone, 2,4′-dihydroxydiphenylsulfone,2,2′,5,5′-tetrahydroxydiphenylsulfone,3,3′,5,5′-tetramethyl-4,4′-dihydoxydiphenylsulfone, hydroxyquinonecarboxylic acid and salts thereof, 2,3-dihydroxy benzoic acid,2,4-dihydroxy benzoic acid, 2,5-dihydroxy benzoic acid, 2,6-dihydroxybenzoic acid, 3,5-dihydroxy benzoic acid, 1,4-hydroquinone sulfonic acidand salts thereof, 4,5-hydroxybenzene-1,3-disulfonic acid and saltsthereof, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene,2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene,2,3-dihydroxynaphthalene, 1,5-dihydroxynaphthalene-2,6-dicarboxylicacid, 1,6-dihydroxynaphthalene-2,5-dicarboxylic acid,1,5-dihydroxynaphthoic acid, 1,4-dihydroxy-2-phenyl naphthoate,4,5-dihydroxynaphthalene-2,7-disulfonic acid and salts thereof,1,8-dihydroxy-3,6-naphthalenedisulfonic acid and salts thereof,6,7-dihydroxy-2-naphthalenesulfonic acid and salts thereof,1,2,3-trihydroxybenzene (pyrogallol), 1,2,4-trihydroxybenzene,5-methyl-1,2,3-trihydroxybenzene, 5-ethyl-1,2,3-trihydroxybenzene,5-propyl-1,2,3-trihydroxybenzene, trihydroxy benzoic acid,trihydroxyacetophenone, trihydroxybenzophenone, trihydroxybenzaldehyde,trihydroxyanthraquinone, 2,4,6-trihydroxybenzene,tetrahydroxy-p-benzoquinone, tetrahydroxyanthraquinone, and the like.

Among these hydroxy group-containing aromatic compounds, a compoundcontaining a sulfo group and/or a carboxy group as anion groups whichare able to dope the π conjugated conductive polymer is preferred inview of conductivity.

Among these hydroxy group-containing aromatic compounds, a compoundrepresented by the above formula (1) is preferred in view of superiorconductivity and stability.

Specific examples of R in formula (1) include alkyl groups such asmethyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, n-hexyl, i-hexyl,t-hexyl, and sec-hexyl groups; alkenyl groups such as vinyl, propenyl,and butenyl groups; cycloalkyl groups such as a cyclohexyl andcyclopentyl groups; cycloalkenyl groups such as cyclohexenyl group; arylgroups such as phenyl and naphthyl groups; aralkyl groups such as benzyland phenethyl groups; and the like.

The content of the hydroxy group-containing aromatic compound ispreferably 0.05 to 10 mol, more preferably 0.3 to 5 mol to 1 mol of thepolyanion. If the content of the hydroxy group-containing aromaticcompound is less than 0.05 mol, conductivity and heat resistance may beinsufficient. If the content of the hydroxy group-containing aromaticcompound is more than 10 mol, the content of the π conjugated conductivepolymer in the conductive composition decreases making it difficult toobtain sufficient conductivity, and then the properties of theconductive composition, the antistatic coating material, or the solidelectrolyte layer of the capacitor may be changed.

(Dopant)

Dopants other than polyanion dopants may also be added to improve theelectric conductivity and heat stability. If the oxidation-reductionpotential of the π conjugated conductive polymers can be changed, theother dopants may be donors or acceptors.

(Donor Dopant)

Examples of donor dopants include alkali metals such as sodium,potassium, and the like; alkali-earth metals such as calcium, magnesium,and the like; quaternary amine compounds such as tetramethylammonium,tetraethylammonium, tetrapropylammonium, tetrabutylammonium,methyltriethylammonium, dimethyldiethylammonium, and the like.

(Acceptor Dopant)

Examples of acceptor dopants include halogen compounds, Lewis acids,protonic acids, organic cyano compounds, organic metal compounds, andthe like.

Examples of halogen compounds include chlorine (Cl₂), bromine (Br₂),iodine (I₂), iodine chloride (ICl), iodine bromide (IBr), iodinefluoride (IF), and the like.

Examples of Lewis acids include PF₅, AsF₅, SbF₅, BF₅, BCl₅, BBr₅, SO₃,and the like.

Examples of organic cyano compounds include compounds containing two ormore cyano groups in the conjugated bond such as tetracyanoethylene,tetracyanoethyleneoxide, tetracyanobenzene, dichlorodicyanobenzoquinone(DDQ), tetracyanoquinodimethane, tetracyanoazanaphthalene, and the like.

The protonic acids include inorganic acids and organic acids. Examplesof inorganic acids include hydrochloric acid, sulfuric acid, nitricacid, phosphoric acid, borohydrofluoric acid, hydrofluoric acid,perchloric acid, and the like. Examples of organic acids include organiccarboxylic acids, phenols, organic sulfonic acids, and the like.

The organic carboxylic acid may be those having one or more carboxygroups in the aliphatic, aromatic, or cyclic aliphatic series. Examplesof the organic carboxylic acids include formic acid, acetic acid, oxalicacid, benzoic acid, phthalic acid, maleic acid, fumaric acid, malonicacid, tartaric acid, citric acid, lactic acid, succinic acid,monochloroacetic acid, dichloroacetic acid, trichloroacetic acid,trifluoroacetic acid, nitroacetic acid, triphenylacetic acid, and thelike.

As organic sulfonic acids, those containing one, two or more sulfogroups in aliphatic, aromatic, and cyclic aliphatic compound or polymerscontaining sulfo groups can be used.

Examples of organic sulfonic acids containing one sulfo group includemethanesulfonic acid, ethanesulfonic acid, 1-propanesulfonic acid,1-butanesulfonic acid, 1-hexanesulfonic acid, 1-heptanesulfonic acid,1-octanesulfonic acid, 1-nonanesulfonic acid, 1-decanesulfonic acid,1-dodecanesulfonic acid, 1-tetradecanesulfonic acid,1-pentadecanesulfonic acid, 2-bromoethanesulfonic acid,3-chloro-2-hydroxypropanesulfonic acid, trifluoromethanesulfonic acid,colistinmethanesulfonic acid, 2-acrylamide-2-methylpropanesulfonic acid,aminomethanesulfonic acid, 1-amino-2-naphthol-4-sulfonic acid,2-amino-5-naphthol-7-sulfonic acid, 3-aminopropanesulfonic acid,N-cyclohexyl-3-aminopropanesulfonic acid, benzenesulfonic acid,p-toluenesulfonic acid, xylenesulfonic acid, ethylbenzenesulfonic acid,propylbenzenesulfonic acid, butylbenzenesulfonic acid,pentylbenzenesulfonic acid, hexylbenzenesulfonic acid,heptylbenzenesulfonic acid, octylbenzenesulfonic acid,nonylbenzenesulfonic acid, decylbenzenesulfonic acid,undecylbenzenesulfonic acid, dodecylbenzenesulfonic acid,pentadecylbenzenesulfonic acid, hexadecylbenzenesulfonic acid,2,4-dimethylbenzenesulfonic acid, dipropylbenzenesulfonic acid,butylbenzensulfonic acid, 4-aminobenzenesulfonic acid,o-aminobenzenesulfonic acid, m-aminobenzenesulfonic acid,4-amino-2-chrolotoluene-5-sulfonic acid,4-amino-3-methylbenzene-1-sulfonic acid,4-amino-5-methoxy-2-methylbenzenesulfonic acid,2-amino-5-methylbenzene-1-sulfonic acid,5-amino-2-methylbenzene-1-sulfonic acid,4-amino-3-methylbenzene-1-sulfonic acid,4-acetamide-3-chlorobenzenesulfonic acid, 4-chrolo-3-nitrobenzensulfonicacid, p-chlorobenzenesulfonic acid, naphthalenesulfonic acid,methylnaphthalenesulfonic acid, propylnaphthalenesulfonic acid,butylnaphthalenesulfonic acid, pentylnaphtalenesulfonic acid,dimethylnaphthalenesulfonic acid, 4-amino-1-naphthalenesulfonic acid,8-chloronaphthalene-1-sulfonic acid, naphthalenesulfonic acid formalincondensation polymer, melaminesulfonic acid formalin condensationpolymer, anthraquinonesulfonic acid, pyrenesulfonic acid, and the like.Furthermore, metal salts thereof can also be used.

Examples of organic sulfonic acids containing two or more sulfo groupsinclude ethanedisulfonic acid, butanedisulfonic acid, pentanedisulfonicacid, decanedisulfonic acid, o-benzenedisulfonic acid,m-benzenedisulfonic acid, p-benzenedisulfonic acid, toluenedisulfonicacid, xylenedisulfonic acid, chlorobenzenedisulfonic acid,fluorobenzenedisulfonic acid, dimethylbenzenedisulfonic acid,diethylbenzenedisulfonic acid, aniline-2,4-disulfonic acid,aniline-2,5-disulfonic acid, 3,4-dihydroxy-1,3-benzene disulfonic acid,naphthalenedisulfonic acid, methylnaphthalenedisulfonic acid,ethylnaphthalenedisulfonic acid, pentadecylnaphthalenedisulfonic acid,3-amino-5-hydroxy-2,7-naphthalenedisulfonic acid,1-acetoamide-8-hydroxy-3,6-naphthalenedisulfonic acid,2-amino-1,4-benzenedisulfonic acid, 1-amino-3,8-naphthalenedisulfonicacid, 3-amino-1,5-naphthalenedisulfonic acid,8-amino-1-naphthol-3,6-disulfonic acid,4-amino-5-naphthol-2,7-disulfonic acid,4-acetamide-4′-isothiocyanatostilbene-2,2′-disulfonic acid,4-acetoamide-4′-maleimidylstilbene-2,2′-disulfonic acid, naphthalenetrisulfonic acid, dinaphthylnethanedisulfonic acid,anthraquinonedisulfonic acid, anthracenesulfonic acid, and the like.Furthermore, metal salts thereof can also be used.

The conductive composition of the present invention may be composed ofthe above-described three components, and a binder resin may becontained in the conductive composition in order to control coatingformability, strength, and the like of a coating formed from theconductive composition. Furthermore, it is preferable that theantistatic coating material contains a binder resin because the scratchresistance and surface hardness of a coating are increased and theadhesion with a base is improved. When the antistatic coating materialcontains a binder resin, the pencil hardness (JIS K 5400) of theantistatic coating formed from the antistatic coating material is easilymade to HB or harder. Namely, the binder resin functions as a hard coatcomponent.

As binder resins, they may be thermosetting resins or thermoplasticresins if they are compatible with or mixable/dispersible in eachcomponent in the conductive composition or in the antistatic coatingmaterial. Examples of binder resins include polyesters such aspolyethylene terephthalate, polybutylene terephthalate, polyethylenenaphthalate, and the like; polyimides such as polyimide, polyamideimide,and the like; polyamides such as polyamide 6, polyamide 6, 6, polyamide12, polyamide 11, and the like; fluororesins such as polyvinylidenefluoride, polyvinyl fluoride, polytetrafluoroethylene,ethylenetetrafluoroethylene copolymer, polychlorotrifluoroethylene, andthe like; vinyl resins such as polyvinyl alcohol, polyvinyl ether,polyvinyl butyral, polyvinyl acetate, polyvinyl chloride, and the like;epoxy resin; oxetane resin; xylene resin; aramide resin; polyimidesilicone; polyurethane; polyurea; melamine resin; phenol resin;polyether; acrylic resin, and their copolymers.

These binder resins may be dissolved in organic solvents, made intosolutions by imparting functional groups such as a sulfo or carboxylgroup to the resins, or dispersed in water by emulsification and thelike.

If necessary, curing agents such as a crosslinking agent, polymerizationinitiator, and the like, a polymerization accelerator, solvent,viscosity modifier, or the like can be added.

Among these binder resins, any one or more of polyurethane, polyester,acrylic resin, polyamide, polyimide, epoxy resin, polyimide silicone,and melamine resin are preferably used because these are easy to mix.Moreover, acrylic resins are suited to such purposes as an opticalfilter because they have high hardness and excellent transparency.

Furthermore, the acrylic resin preferably contains a heat-curable orphoto-curable liquid polymer.

The heat-curable liquid polymer can be, for example, a reactive polymeror a self-crosslinkable polymer.

The reactive polymers are polymers obtained by polymerizing a monomerwith a substituent such as hydroxyl, carboxyl, anhydride, oxetane,glycidyl, and amino groups. Examples of the monomers includepolyfunctional alcohols such as ethylene glycol, diethylene glycol,dipropylene glycol, glycerin, and the like; carboxylic acid compoundssuch as malonic acid, succinic acid, glutamic acid, pimelic acid,ascorbic acid, phthalic acid, acetylsalicylic acid, adipic acid,isophthalic acid, benzoic acid, m-toluic acid, and the like; acidanhydrides such as maleic acid anhydride, phthalic acid anhydride,dodecylsuccinic anhydride, dichloromaleic anhydride, tetrachlorophthalicanhydride, tetrahydrophthalic anhydride, pyromellitic acid anhydride,and the like; oxetane compounds such as 3,3-dimethyloxetane,3,3-dichloromethyloxetane, 3-methyl-3-hydroxymethyloxetane,azidomethylmethyloxetane, and the like; glycidyl ether compounds such asbisphenol A diglycidyl ether, bisphenol F diglycidyl ether, phenolnovolac polyglycidyl ether, N,N-diglycidyl-p-aminophenol glycidyl ether,tetrabromobisphenol A diglycidyl ether, hydrogenated bisphenol Adiglycidyl ether (i.e., 2,2-bis(4-glycidyloxycyclohexyl)propane), andthe like; glycidyl amine compounds such as N,N-diglycidylaniline,tetraglycidyldiaminodiphenylmethane,N,N,N,N-tetraglycidyl-m-xylylenediamine, triglycidyl isocyanurate,N,N-diglycidyl-5,5-dialkylhydantoin, and the like; amine compounds suchas diethylenetriamine, triethylenetetramine, dimethylaminopropylamine,N-aminoethylpiperazine, benzyldimethylamine,tris(dimethylaminomethyl)phenol, DHP30-tri(2-ethyl hexoate),metaphenylenediamine, diaminodiphenylmethane, diaminodiphenyl sulfone,dicyanodiamide, boron trifluoride, monoethylamine, methanediamine,xylenediamine, ethylmethylimidazole, and the like; glycidyl compoundsbased on epichlorohydrin of bisphenol A in compounds containing two ormore oxirane rings in a molecule or their analogs.

At least difunctional or higher crosslinking agents are used in thereactive polymers. The crosslinking agents include, for example,melamine resin, epoxy resin, metal oxides, and the like. Examples of themetal oxides include basic metallic compounds such as Al(OH)₃,Al(OOC.CH₃)₂(OOCH), Al(OOC.CH₃)₂, ZrO(OCH₃), Mg(OOC.CH₃), Ca(OH)₂,Ba(OH)₃, and the like that can be properly used.

The self-crosslinkable polymers are polymers that self-crosslink witheach other by functional groups due to heating, and include, forexample, glycidyl and carboxyl groups or N-methylol and carboxy groups.

The photo-curable liquid polymer may be, for example, oligomers orprepolymers such as polyester, epoxy resin, oxetane resin, polyacryl,polyurethane, polyimide, polyamide, polyamideimide, polyimide silicone,and the like.

Examples of monomer units constituting a photo-curable liquid polymerinclude monofunctional monomers and polyfunctional monomers of acrylatessuch as bisphenol A ethylene oxide-modified diacrylate,dipentaerythritol hexa(penta)acrylate, dipentaerythritol monohydroxypentacrylate, dipropylene glycol diacrylate, trimethylolpropanetriacrylate, glycerin propoxytriacrylate, 4-hydroxybutyl acrylate,1,6-hexanediol diacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropylacrylate, isobornyl acrylate, polyethylene glycol diacrylate,pentaerythritol triacrylate, tetrahydrofurfuryl acrylate,trimethylolpropane triacrylate, tripropylene glycol diacrylate, and thelike; methacrylates such as tetraethylene glycol dimethacrylate, alkylmethacrylates, allyl methacrylate, 1,3-butylene glycol dimethacrylate,n-butyl methacrylate, benzyl methacrylate, cyclohexyl methacrylate,diethylene glycol dimethacrylate, 2-ethylhexyl methacrylate, glycidylmethacrylate, 1,6-hexanediol dimethacrylate, 2-hydroxyethylmethacrylate, isobornyl methacrylate, lauryl methacrylate, phenoxyethylmethacrylate, t-butyl methacrylate, tetrahydrofurfuryl methacrylate,trimethylolpropane trimethacrylate, and the like; glycidyl ethers suchas allylglycidyl ether, butylglycidyl ether, higher alcohol glycidylether, 1,6-hexanediolglycidyl ether, phenylglycidyl ether,stearylglycidyl ether, and the like; acryl (methacryl) amides such asdiacetoneacrylamide, N,N-dimethylacrylamide,dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide,methacrylamide, N-methylolacrylamide, N,N-dimethylmethacrylamide,acryloylmorpholine, N-vinylformamide, N-methylacrylamide,N-isopropylacrylamide, N-t-butylacrylamide, N-phenylacrylamide,acryloylpiperizine, 2-hydroxyethyl acrylamide, and the like; vinylethers such as 2-chloroethylvinyl ether, cyclohexylvinyl ether,ethylvinyl ether, hydroxybutylvinyl ether, isobutylvinyl ether,triethyleneglycol vinyl ether, and the like; vinyl carboxylates such asvinyl butyrate, vinyl monochloroacetate, vinyl pivalate, and the like.

The photo-curable liquid polymer is cured with a photopolymerizationinitiator. The photopolymerization initiator can be, for example,acetophenones, benzophenones, Michler's benzoylbenzoates, α-amyloximeesters, tetramethylthiuram monosulfides, or thioxanthones. Aphotosensitizer such as n-butylamine, triethylamine, andtri-n-butylphosphine can be mixed.

Examples of cationic polymerization initiators include aryl diazoniumsalts, diaryl halonium salts, triphenyl sulfonium salts,silanol/aluminum chelate, α-sulfonyloxyketones, and the like.

Precursor compounds or monomers forming a binder resin may be containedin place of the above-described binder resin. The binder resin can beformed by polymerizing the precursor compounds or monomers.

In the conductive composition, additives may be contained as well as thebinder resin. Additives which can be mixed with each component of theconductive composition are used, and examples of additives include asurface active agent, an antifoaming agent, a coupling agent, aneutralizing agent, an antioxidant, and the like.

Examples of surface active agents include an anionic surface activeagent such as carboxylate, sulfonate, sulfate salt, phosphate salt, andthe like; a cationic surface active agent such as an amine salt, aquaternary ammonium salt, and the like; an amphoteric surface activeagent such as a carboxybetaine, an aminocarboxylate salt, an imidazoliumbetaine, and the like; and a nonionic surface active agent such as apolyoxyethylene alkylether, a polyoxyethylene glycerine fatty acidester, an ethylene glycol fatty acid ester, a polyoxyethylene fatty acidamide, and the like.

Examples of antifoaming agents include a silicone resin, apolydimethylsiloxane, a silicone resin, and the like.

Examples of coupling agents include a silane coupling agent containingvinyl, amino, epoxy groups, and the like.

Examples of neutralizing agents include an alkali compound such asammonia, sodium hydroxide, or the like and a nitrogen-containingcompound such as primary amines, secondary amines, tertiary amines, andthe like.

Examples of antioxidants include a phenolic antioxidant, an amineantioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant,saccharides, vitamins, and the like.

Since each conductive composition, antistatic coating material, andsolid electrolyte layer of a capacitor contains a hydroxygroup-containing aromatic compound, high conductivity and heatresistance are shown. It is considered that these properties can beobtained for the following reasons.

Since the π conjugated conductive polymer is in a highly oxidized state,it is considered that radicals will be formed by oxidative degradationof a portion of the polymer due to the external environment such asheat, and then degradation progresses according to a radical chainreaction. On the other hand, the hydroxy group-containing aromaticcompound has a strong interaction between the hydroxy groups and thearomatic ring, and tends to release hydrogen from the compound.Therefore, hydrogen released from the hydroxy group-containing aromaticcompound can deactivate radicals formed by oxidative degradation of theπ conjugated conductive polymer. Accordingly, the radical chain reactionis stopped and progression of degradation is suppressed, and thus theheat resistance and stability should be high. This effect occurs whenthe aromatic compound contains two or more hydroxy groups.

The hydroxy group-containing aromatic compound tends to interact withanion groups in the polyanion. It is considered that this interactioncan shorten the distance between polyanions, and accordingly, thedistance between the π conjugated conductive polymers, adsorbed on thepolyanion by doping, each other can be also shortened. As a result, theenergy for hopping, which is an electric conduction phenomenon between πconjugated conductive polymers, is reduced, and thus the total electricresistance can be reduced (conductivity can increase).

(Production Methods)

(Conductive Composition)

An example of a production method of a conductive composition accordingto the present invention is explained.

In the production method of a conductive composition of this example,first, in a polymerization step, a precursor monomer forming a πconjugated conductive polymer is dispersed or dissolved in a solvent inthe presence of a polyanion to polymerize by a chemical oxidativepolymerization. Specifically, a polyanion, a precursor monomer, and anoxidant and/or oxidative polymerization catalyst for polymerizing theprecursor monomer by the chemical oxidative polymerization are prepared.The precursor monomer and oxidant and/or oxidative polymerizationcatalyst are added to the polyanion maintained at a constant temperatureand are reacted for a predetermined time while stirring to polymerizethe precursor monomer by the chemical oxidative polymerization. Anoperation method, a sequence of the operation, reaction conditions, andthe like are not limited in the polymerization step.

A mixed solution having a predetermined concentration may be prepared byadding a solvent to the polyanion, precursor monomer, oxidant and/oroxidative polymerization catalyst beforehand.

When the π conjugated conductive polymer is polymerized by the chemicaloxidative polymerization, the main chain of the π conjugated conductivepolymer grows along the main chain of the polyanion and then the πconjugated conductive polymer forms a bipolaron structure under thehighly oxidized conditions. Accordingly, it is considered that aniongroups of the polyanion are doped with the π conjugated conductivepolymer to form a salt of the polyanion and the π conjugated conductivepolymer. When the polyanion has sulfo groups, a salt of the polyanionstrongly bonding with the π conjugated conductive polymer can be formed.Since the π conjugated conductive polymer is strongly attracted to themain chain of the polyanion, the π conjugated conductive polymerarranged with regularity by growing along the main chain of thepolyanion can be easily obtained.

In the polymerization step, a mixed solution containing the polyanionand the π conjugated conductive polymer is obtained.

A reaction terminator to stop the polymerization reaction may be added,if necessary, after the polymerization step has been completed.Furthermore, excess oxidant and/or oxidative polymerization catalyst andreaction by-products may be removed and ion exchange may be carried outafter the polymerization step has been completed.

Next, in an addition step, a predetermined amount of a hydroxygroup-containing aromatic compound is added in the mixed solutionobtained in the polymerization step and mixed so as to form a uniformsolution.

As an addition process of the hydroxy group-containing aromaticcompound, a process for adding the hydroxy group-containing aromaticcompound as it is and a process for adding a solution in which thehydroxy group-containing aromatic compound is dissolved or dispersed ina solvent are exemplified. In view of the ease of mixing with theabove-described mixed solution, the process for adding a solution inwhich the hydroxy group-containing aromatic compound is dissolved ordispersed in a solvent is preferred. Solvents for dissolving ordispersing the hydroxy group-containing aromatic compound are notespecially limited and the above-described solvents can be used.Solvents may differ from the solvent used in the mixed solution.

Subsequently, in a filtration step, a conductive composition is obtainedby partially removing free ions by an ultrafiltration method. In theproduction method of the conductive composition of the presentinvention, the filtration step is an optional step and may be omitted.

In the ultrafiltration method, a polymer membrane (an ultrafiltrationmembrane) formed with a constant bore diameter is provided on a porousmaterial and the solution is circulated. The ultrafiltration membrane isinserted to produce a differential pressure between the circulatedsolution and the permeated solution; therefore, a part of solution atthe circulated solution side penetrates to the permeated solution sideand releases the pressure at the circulated solution side. Particlessmaller than the bore diameter of the ultrafiltration membrane and apart of the dissolved ions or the like contained in the circulatedsolution are transferred to the permeated solution side based on theabove phenomenon to be removed. This method is a dilution method andimpurities can be easily removed by repeating this dilution.

The ultrafiltration membrane to be used is suitably selected dependingupon the diameter of particles to be removed and ion species, and anultrafiltration membrane having a range of molecular weight cut off of1000 to 100000 is preferably used.

Since the obtained π conjugated conductive polymer contains a grownπ-conjugate system in the main chain, π conjugated conductive polymersgenerally have insoluble and infusible properties. In the π conjugatedconductive polymer solution obtained by dissolution or dispersion, sincethe π conjugated conductive polymer is self-coordinated by removingsolvents, heating, doping, or the like when forming a film, the πconjugated conductive polymer may be insoluble. Therefore, solventsshould be appropriately selected.

The above-described production method of the conductive compositioncomprises a polymerization step for polymerizing a precursor monomerforming a π conjugated conductive polymer in the presence of polyanionby a chemical oxidative polymerization, and an addition step for addinga hydroxy group-containing aromatic compound, and then a conductivecomposition comprising the π conjugated conductive polymer, thepolyanion, and the hydroxy group-containing aromatic compound isobtained. Since the conductive composition comprises the hydroxygroup-containing aromatic compound, superior conductivity and stabilityare shown.

(Antistatic Coating Material)

To produce an antistatic coating material, first, a polyanion isdissolved in a solvent for dissolving it, a precursor monomer of a πconjugated conductive polymer and, as necessary, a dopant are added andfully stirred and mixed. Next, an oxidant is added dropwise into theobtained mixture to advance a polymerization and obtain complexes of thepolyanion and π conjugated conductive polymer. Subsequently, theoxidant, residual monomer, and by-products are removed from thecomplexes to purify, and then, dissolved in an appropriate solvent. Ahydroxy group-containing aromatic compound and, as necessary, a dopantand a binder resin are added to obtain an antistatic coating material.

Purification methods are not specially limited, for example,reprecipitation method, ultrafiltration method or the like can be used.Among these, the ultrafiltration method is simple and thus preferable.The ultrafiltration method is a method wherein a liquid in a solution ispermeated and filtered through a porous ultrafiltration membrane whilecirculating the solution on the ultrafiltration membrane. In thismethod, the ultrafiltration membrane is inserted to produce adifferential pressure between the circulated solution and the permeatedsolution; therefore, a part of solution at the circulated solution sidepenetrates to the permeated solution side and release the pressure atthe circulated solution side. Particles smaller than the bore diameterof the ultrafiltration membrane and a part of dissolved ions transfer tothe permeated solution side according to the penetration of thiscirculated solution. Therefore, these particles and dissolved ions canbe removed. The ultrafiltration membrane to be used is properly selecteddepending upon diameter of particles to be removed and ion species, andthe ultrafiltration membrane having a range of molecular weight cut offof 1000 to 100000 is preferably used.

(Antistatic Coating)

An antistatic coating is formed by applying an antistatic coatingmaterial on a base. Examples of methods for applying the antistaticcoating material include dipping, comma coating, spray coating, rollcoating, gravure printing, and the like. Bases are not speciallylimited, and resin moldings easy to cause static electricity, especiallyresin films such as polyester film, triacetyl cellulose (TAC) film, andthe like are suitable.

After the application, the solvent is removed by heating, or the coatingmay be cured by heat or light. As heating methods in case of heating,for example, common methods such as hot-air heating or infrared heatingcan be adopted. As methods for irradiating a light in case of forming acoating film by photohardening, for example, a method for irradiatingultraviolet ray from light sources such as ultrahigh-pressure mercuryvapor lamp, high-pressure mercury vapor lamp, low-pressure mercury vaporlamp, carbon arc, xenon arc, metal halide lamp, and the like can beadopted.

Since the antistatic coating comprises the hydroxy group-containingaromatic compound, the conductivity remarkably increases and thedegradation of the π conjugated conductive polymer is suppressed.

More specifically, the conductivity is about 0.001 to 100 S/cm when nohydroxy group-containing aromatic compound is contained, on the otherhand, the conductivity is about 10 to 2000 S/cm when a hydroxygroup-containing aromatic compound is contained.

When the antistatic coating is used in an optical field, especially,used for an optical filter and an optical information recording mediumdescribed later, the transparency is preferably high. More specifically,the total light transmittance (JIS Z 8701) is preferably 85% or above,more preferably 90% or above, and especially preferably 96% or above.

The haze (JIS K 6714) is preferably 5% or below, more preferably 3% orbelow, and especially preferably 1% or below.

The surface hardness (pencil hardness) of the antistatic coating ispreferably HB or harder when the antistatic coating also serves as ahard coat layer. The pencil hardness can be adjusted by the thickness ofcoating film.

It is preferable that the surface resistance of the antistatic coatingis properly adjusted in accordance with optical characteristics.Usually, if the surface resistance is about 1×10³ to 1×10¹²Ω, it isapplicable to the antistatic purpose.

The light transmittance, haze, and surface resistance of the coatingfilm can be adjusted by the thickness of the coating film.

The total light transmittance, haze, and surface resistance of thecoating film can be adjusted by the thickness of the antistatic coating.It is preferable that a binder resin is not contained when a low surfaceresistance value is desired. However, it is preferable that a binderresin is contained to lower the cost or improve the adhesion to a base.

(Antistatic Film)

An antistatic film has a film base and the above antistatic coatingformed on at least one side of the film base.

Examples of film bases include low-density polyethylene film,high-density polyethylene film, ethylene-propylene copolymer film,polypropylene film, ethylene-vinylacetate copolymer film,ethylene-methyl methacrylate copolymer film, polyethylene terephthalate(PET) film, polybutylene terephthalate (PBT) film, polyethylenenaphthalate (PEN) film, polyimide film, 6-nylon film, 6,6-nylon film,polymethyl methacrylate film, polystyrene film,styrene-acrylonitrile-butadiene copolymer film, polyacrylonitrile film,cellulose triacetate (TAC) film, cellulose propionate film, polyvinylchloride film, polyvinylidene chloride film, polyvinylidene fluoridefilm, polytetrafluoroethylene film, polyvinyl alcohol film,ethylene-vinyl alcohol copolymer film, polycarbonate film, polysulfonefilm, polyether sulfone film, polyether ether ketone film, polyphenyleneoxide film, and the like.

The surface of these film bases are usually oleophilic, when anantistatic coating material dissolved in an aqueous solvent is applied,the application is difficult. Therefore, when an antistatic coatingmaterial dissolved in an aqueous solvent is applied, it is preferable togive etching treatments such as sputtering, corona discharge, flame,ultraviolet irradiation, electron ray irradiation, chemical reaction,oxidation, and the like or hydrophilic treatments such as primercoating, and the like. Moreover, the surface may also be dust removedand cleaned by solvent washing, ultrasonic washing, or the like.

(Optical Filter)

An embodiment example of an optical filter of the present invention isexplained.

The optical filter of this embodiment example is shown in FIG. 1. Thisoptical filter 1 comprises a film base 10, an antistatic coating 20formed on the film base 10, and an antireflecting layer 30 formed on theantistatic coating 20. The antistatic coating 20 in this optical filter1 functions as a hard coat layer.

When the optical filter 1 is provided on the surface of a display, atransparent adhesive layer is provided on the surface of the film base10 in the optical filter 1, and the optical filter 1 and the surface ofthe display are provided via the adhesive layer.

Various plastic films having transparency can be used as the film base10. Examples of the transparent plastic films include films made ofpolyethylene terephthalate, polyimide, polyether sulfone, polyetherether ketone, polycarbonate, polypropylene, polyamide, acrylamide,cellulose propionate, and the like.

Moreover, it is preferable that etching treatments such as sputtering,corona discharge, flame, ultraviolet irradiation, electron rayirradiation, chemical reaction, oxidation, and the like or hydrophilictreatments such as primer coating are given to the surface of film base10. If such treatments are given to the surface, the adhesion to theantistatic coating 20 can be further increased.

Furthermore, the surface of film base 10 may also be dust removed orcleaned by solvent washing, ultrasonic washing, or the like, asnecessary, before the antistatic coating 20.

The antistatic coating 20 is a membrane formed from an antistaticcoating material as described above, and the membrane functions as ahard coat layer. Accordingly, as described above, the surface hardness(pencil hardness) of this antistatic coating 20 is preferably HB orharder. The total light transmittance (JIS Z 8701) of antistatic coating20 is preferably 85% or above, more preferably 90% or above, andespecially preferably 96% or above for optical purposes. The haze (JIS K6714) is preferably 5% or below, more preferably 3% or below, andespecially preferably 1% or below.

The antireflecting layer 30 is a layer for preventing the reflection oflight. This layer may be a single layer or a multilayer. In case of asingle layer, the refractive index is preferably in a range of 1.38 to1.45, and the thickness of optical film is preferably in a range of 80to 100 nm.

The antireflecting layer 30 can be formed by either dry processes or wetprocesses. Examples of dry processes include physical depositionprocesses such as electron-beam vapor deposition process, dielectricheating vapor deposition process, resistance heating vapor depositionprocess, sputtering process, ion plating process, and the like, andplasma CVD process. When the antireflecting layer 30 is formed by thedry processes, for example, inorganic compounds such as silicon oxide,magnesium fluoride, niobium oxide, titanium oxide, tantalum oxide,aluminum oxide, zirconium oxide, indium oxide, tin oxide, and the likecan be used as components of the antireflecting layer 30.

As wet processes, for example, processes wherein a coating containingcurable compounds is applied by well-known methods such as commacoating, spray coating, roll coating, gravure printing, and the like aregiven. When the antireflecting layer 30 is formed by the wet processes,for example, fluorine compounds such as fluorine-containing organiccompounds, fluorine-containing organosilicon compounds,fluorine-containing inorganic compounds, and the like can be used as acurable compound.

In the optical filter 1, an antifouling layer may be further provided onthe antireflecting layer 30. If the antifouling layer is provided, itprevents the adherence of dust and dirt or facilitates to remove dustand dirt even if they adhere to.

The antifouling layer is not specially limited if it does not hinder theantireflection function of the antireflecting layer 30, can show highwater repellence and high oil repellence, and prevent the adherence ofcontaminants. The antifouling layer may be a layer made of organiccompounds or a layer made of inorganic compounds. For example, a layercontaining organosilicon compounds with a perfluorosilane group or afluorocycloalkyl group, or a layer containing organofluorine compoundscan be used.

The processes for forming the antifouling layer can be properly selectedaccording to their kinds, for example, physical vapor depositionprocesses or chemical vapor deposition processes such as depositionprocess, sputtering process, ion plating process; vacuum processes suchas plasma polymerization process; microgravure process, screen coatingprocess, dip coating process, and the like can be adopted.

The optical filter 1 described above is excellent in transparency andalso excellent in adhesion to the film base 10 because the antistaticcoating 20 protecting the film base 10 is formed and the antistaticcoating 20 is formed from the above antistatic coating materials.Moreover, this optical filter 1 is a filter excellent in stability ofantistatic property and its surface is hard to be adhered by dust.

Then, such an optical filter 1 is suitably used as an antireflectingfilm, an infrared absorption film, an electromagnetic wave absorptionfilm, and the like for liquid crystal displays and plasma displays.

Moreover, the optical filter of the present invention is not limited tothe above-mentioned embodiment examples, if the optical filter has anantistatic coating formed from the above antistatic coating materials.

For example, a polarizing plate can also be used in place of the filmbase. For example, a polarizing plate is obtained by laminatingprotecting films on one side or both sides of a polyvinyl alcohol resinfilm in which a dichromic colorant is absorbed and oriented. Asdichromic colorants, iodine, dichromic dyes can be used. Such an opticalfilter can be provided at the uppermost surface of a liquid crystaldisplay.

(Optical Information Recording Medium)

An embodiment example of an optical information recording medium of thepresent invention is explained.

The optical information recording medium of this embodiment example isshown in FIG. 2. This optical information recording medium 2 is arewrite-type disk and has a structure in which a disk-like transparentresin base 40, a first dielectric layer 50, an optical informationrecording layer 60, a second dielectric layer 70, a metal reflectinglayer 80, and an antistatic coating 90 are formed in order.

As materials constructing the first dielectric layer 50 and the seconddielectric layer 70, for example, inorganic materials such as SiN, SiO,SiO₂, Ta₂O₅, or the like can be used. These dielectric layers are formedin a thickness of 10 to 500 nm by well-known means such as vacuum vapordeposition process, sputtering process, ion plating process, and thelike.

As materials constructing the optical information recording layer 60,for example, inorganic photomagnetic recording materials such as Tb—Fe,Tb—Fe—Co, Dy—Fe—Co, Tb—Dy—Fe—Co, and the like; inorganic phase-changerecording materials such as TeOx, Te—Ge, Sn—Te—Ge, Bi—Te—Ge, Sb—Te—Ge,Pb—Sn—Te, Tl—In—Se, and the like; and organic colorants such as cyaninecolorants, polymethine colorants, phthalocyanine colorants, merocyaninecolorants, azulene colorants, squalium colorants, and the like are used.

When the optical information recording layer 60 is made of inorganicphotomagnetic recording materials, it can be formed in a thickness of 10to 999 nm by well-known means such as vacuum vapor deposition process,sputtering process, ion plating process, and the like. When the opticalinformation recording layer 60 is made of organic colorants, a solutiongiven by dissolving an organic colorant in a solvent such as acetone,diacetone alcohol, ethanol, methanol, and the like can be formed in athickness of 10 to 999 nm by well-known printing process or coatingprocess.

The metal reflecting layer 80 exhibits light reflectivity and iscomposed of metals such as Al, Cr, Ni, Ag, Au, and the like and oxidesthereof, nitrides thereof, and the like separately or by combining twoor more kinds of them. This metal reflecting layer 80 is formed in athickness 2 to 200 nm by sputtering or vacuum deposition process.

The antistatic coating 90 is formed from the above antistatic coatingmaterials. Since the surface hardness of the antistatic coating 90 isset to HB or harder, the antistatic coating 90 can prevent surfacescratch of the optical information recording medium 2 and preventoxidation of the metal reflecting layer 80 as well as the adherence ofdust due to static electricity.

The thickness of antistatic coating 90 is preferably 3 to 15 μm. If thethickness is thinner than 3 μm, the formation of a uniform membranetends to become difficult, sufficient antistatic property, surfacescratch resistance and oxidation resistance of the metal reflectinglayer 80 sometimes cannot be displayed. On the other hand, if thethickness is thicker than 15 μm, it is feared that the internal stressincreases and mechanical properties of the optical information recordingmedium 2 deteriorate.

The antistatic coating 90 is formed by applying an antistatic coatingmaterial on the metal reflecting layer 80 by well-known methods such ascomma coating, spray coating, roll coating, gravure printing, and thelike, and then drying the solvent or curing by heat or UV irradiation.

In the optical information recording medium 2 explained above, theantistatic coating 90 protecting the optical information recording layer60 and the metal reflecting layer 80 is formed, and the antistaticcoating 90 is formed from the above antistatic coating material.Accordingly, the antistatic coating 90 is excellent in transparency inthe range of 780 nm and 635 nm which is a range of wavelength ofread-only laser because the haze is low and the light transmittance ishigh. Moreover, the dust adherence due to static electricity issuppressed and the recording reading errors and writing errors areprevented because the antistatic coating 90 has the antistatic property.

Moreover, the optical information recording medium of the presentinvention is not limited to the above-mentioned embodiment example; theoptical information recording medium may also be a postscript-type disk.For example, the postscript-type disk has a structure in which atransparent resin base (organic base), an optical information recordinglayer, a reflecting metal layer and an antistatic coating are formed inorder.

(Capacitor)

An embodiment example of a capacitor of the present invention and itsproduction method is explained.

FIG. 3 is a diagram showing the construction of a capacitor of thisembodiment example. This capacitor 100 is schematically constructed byhaving an anode 110 composed of a porous valve metal body, a dielectriclayer 120 formed by oxidizing the surface of anode 110, and a cathodeformed on the dielectric layer 120.

<Anode>

Examples of valve metals forming the anode 110 include aluminum,tantalum, niobium, titanium, hafnium, zirconium, zinc, tungsten,bismuth, antimony, and the like. Among these, aluminum, tantalum, andniobium are preferably used. These valve metals can form a densely anddurable dielectric oxide film (dielectric layer) by electrolyticoxidation; therefore, the capacity of capacitor can be stably increased.

As specific examples of anode 110, an anode obtained by etching analuminum foil to increase the surface area and then oxidizing itssurface, an anode obtained by oxidizing the surface of sintered body oftantalum particles or niobium particles and then forming pellets, andthe like are given. The irregularities are formed on the surface ofanodes thus treated.

<Dielectric Layer>

The dielectric layer 120 is formed, for example, by anodic oxidation ofthe surface of metal body 110 in an electrolyte such as an aqueoussolution of ammonium adipate. Accordingly, as shown in FIG. 3, theirregularities are similarly formed at the surface of the dielectriclayer 120 as the anode 110.

<Cathode>

A cathode 130 comprises a solid electrolyte layer 130 a and a conductivelayer 130 b composed of carbon, silver, aluminum, and the like andformed on the solid electrolyte layer 130 a. The solid electrolyte layer130 a comprises a π conjugated conductive polymer, a polyanion, and ahydroxy group-containing aromatic compound.

When the conductive layer 130 b is constructed of carbon, silver, andthe like, it is formed from a conductive paste containing a conductorsuch as carbon, silver, and the like. When the conductive layer 130 b isconstructed of aluminum, it is formed from an aluminum foil.

Moreover, a separator can be provided between the solid electrolytelayer 130 a and the conductive layer 130 b as necessary.

A production method of the capacitor is a method wherein a conductivepolymer solution is applied to the surface of a dielectric layer 120 ofa capacitor intermediate having the anode 110 composed of a porous valvemetal body and the dielectric layer 120 of an oxide film formed byoxidizing the surface of the anode 110 to form the solid electrolytelayer 130 a.

The conductive polymer solution in this production method contains a 7conjugated conductive polymer, a polyanion, a hydroxy group-containingaromatic compound, and a solvent.

To prepare the conductive polymer solution, first, the polyanion isdissolved in a solvent which can dissolve the polyanion, a precursormonomer such as aniline, pyrrole, thiophene, and the like forming the πconjugated conductive polymer is added into the obtained solution. Next,an oxidant is added to polymerize the precursor monomer, subsequently,excess oxidant and precursor monomer are separated and purified. Then,the hydroxy group-containing aromatic compound is added to obtain theconductive polymer solution.

Solvents contained in the conductive polymer solution are not speciallylimited, examples of solvents include alcohol solvents such as methanol,ethanol, isopropyl alcohol (IPA), and the like; amide solvents such asN-methylpyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide(DMF), and the like; ketone solvents such as methyl ethyl ketone (MEK),acetone, cyclohexane, and the like; ester solvents such as ethylacetate, butyl acetate, and the like; toluene, xylene, water, and thelike. They may be used separately or used by mixing. Water and alcoholsolvents with a low environmental load are preferable among them from arecent viewpoint of environmental protection.

Examples of coating methods of the conductive polymer solution includewell-known methods such as coating, dipping, spraying, and the like.Examples of drying methods include well-known methods such as hot-airdrying, and the like.

After the solid electrolyte layer 130 a is formed, the conductive layer130 b can be formed by well-known methods such as a method using acarbon paste or silver paste, and a method providing the cathode at theopposed side via a separator.

In the solid electrolyte layer 130 a, since the particle diameter of theπ conjugated conductive polymer is large, the π conjugated conductivepolymer does not reach to the deepest part of fine voids at the surfaceof dielectric layer of the capacitor intermediate product, sometimes itbecomes difficult to derive a capacity. Therefore, it is preferable thatthe capacity is supplemented by impregnating an electrolyte as necessaryafter the solid electrolyte layer 130 a is formed.

(Electrolytes)

Electrolytes are not specially limited if they have a high conductivity,and well-known electrolytes are dissolved in well-known solvents.

Examples of solvents in the electrolytes include alcohol solvents suchas ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol,glycerin, and the like; lactone solvents such as γ-butyrolactone,γ-valerolactone, δ-valerolactone, and the like; amide solvents such asN-methylformamide, N,N-dimethylformamide, N-methylacetamide,N-methylpyrrolidinone, and the like; nitrile solvents such asacetonitrile, 3-methoxypropionitrile, and the like; water and the like.

Examples of the electrolytes include electrolytes with organic acidssuch as adipic acid, glutaric acid, succinic acid, benzoic acid,isophthalic acid, phthalic acid, terephthalic acid, maleic acid, toluicacid, enanthic acid, malonic acid, formic acid, decane dicarboxylicacids such as 1,6-decane dicarboxylic acid, 5,6-decane dicarboxylicacid, and the like, octane dicarboxylic acids such as 1,7-octanedicarboxylic acid, and the like, azelaic acid, sebacic acid, and thelike, or inorganic acids such as boric acid, polyalcohol complexes ofboric acid obtained from boric acid and polyalcohols, phosphoric acid,carbonic acid, silicic acid, and the like as anion component; andprimary amines (methylamine, ethylamine, propylamine, butylamine,ethylenediamine, and the like), secondary amines (dimethylamine,diethylamine, dipropylamine, methylethylamine, diphenylamine, and thelike), tertiary amines (trimethylamine, triethylamine, tripropylamine,triphenylamine, 1,8-diazabicyclo(5,4,0)-undecene-7, and the like),tetraalkylammoniums (tetramethylammonium, tetraethylammonium,tetrapropylammonium, tetrabutylammonium, methyltriethylammonium,dimethyldiethylammonium, and the like), and the like as cationcomponent.

The above-mentioned production method involves simple processes, issuited to mass production, and is low-cost because the solid electrolytelayer is formed by coating a conductive polymer solution and thendrying. Furthermore, since the conductive polymer solution contains a πconjugated conductive polymer, a polyanion, and a hydroxygroup-containing aromatic compound, the degradation of the π conjugatedconductive polymer in the solid electrolyte layer is suppressed and thehopping energy is reduced. Therefore, the conductivity of the solidelectrolyte layer can be increased, and thus the performance of thecapacitor can be improved.

EXAMPLES

Examples of the present invention are shown below; however, the presentinvention is not limited to the following examples.

Preparation Example 1 Synthesis of Poly(Ethyl Methacrylate SulfonicAcid) (PMAS)

216 g of ethyl methacrylate sodium sulfonate was dissolved in 1000 ml ofion-exchanged water, 1.14 g of ammonium persulfate previously dissolvedin 10 ml of water beforehand was added dropwise over 20 minutes whilestirring at 80° C., and the mixture was continuously stirred for anadditional 12 hours.

1000 ml of sulfuric acid diluted to 10% by weight was added to theobtained poly (ethyl methacrylate sodium sulfonate) solution, about 1000ml of the solution was removed by an ultrafiltration method, 2000 ml ofion-exchanged water was added to the residue, and about 2000 ml of thesolution was removed by the ultrafiltration method. The aboveultrafiltration operation was repeated three times.

Subsequently, about 2000 ml of ion-exchanged water was added to theobtained filtrate and about 2000 ml of the solution was removed by theultrafiltration method. This ultrafiltration operation was repeatedthree times.

The ultrafiltration conditions were as follows (the same was applied tothe other examples).

Molecular cutoff of the ultrafiltration membrane: 30000

Cross flow system

-   -   Feed rate: 3000 ml/min.    -   Membrane partial pressure: 0.12 Pa

Water in the obtained solution was removed under reduced pressure toobtain a colorless solid material.

Preparation Example 2 Synthesis of Polystyrene Sulfonic Acid

206 g of sodium styrene sulfonate was dissolved in 1000 ml ofion-exchanged water, 1.14 g of ammonium persulfate previously dissolvedin 10 ml of water beforehand was added dropwise over 20 minutes whilestirring at 80° C., and the mixture was continuously stirred for anadditional 12 hours.

1000 ml of sulfuric acid diluted to 10% by weight was added to theobtained poly(sodium styrene sulfonate) solution, about 1000 ml of thesolution was removed by the ultrafiltration method, 2000 ml ofion-exchanged water was added to the residue, and about 2000 ml of thesolution was removed by the ultrafiltration method. The aboveultrafiltration operation was repeated three times.

Subsequently, about 2000 ml of ion-exchanged water was added to theobtained filtrate and about 2000 ml of the solution was removed by theultrafiltration method. This ultrafiltration operation was repeatedthree times.

Water in the obtained solution was removed under reduced pressure toobtain a colorless solid material.

Preparation Example 3

14.2 g of 3,4-ethylenedioxythiophene and a solution obtained bydissolving 36.7 g of polystyrene sulfonic acid in 2000 ml ofion-exchanged water were mixed at 20° C.

This mixed solution was maintained to 20° C., 29.64 g of ammoniumpersulfate dissolved in 200 ml of ion-exchanged water and 8.0 g of anoxidation catalyst solution of ferric sulfate were slowly added whilestirring, and then the mixture was stirred and reacted for 3 hours.

2000 ml of ion-exchanged water was added to the obtained solution, andabout 2000 ml of solution was removed by the ultrafiltration method.This operation was repeated three times.

200 ml of sulfuric acid diluted to 10% by weight and 2000 ml ofion-exchanged water were added to the obtained solution, about 2000 mlof the solution was removed by the ultrafiltration method, 2000 ml ofion-exchanged water was added to the residue, and about 2000 ml of thesolution was removed by the ultrafiltration method. The aboveultrafiltration operation was repeated three times.

Subsequently, 2000 ml of ion-exchanged water was added to the obtainedfiltrate and about 2000 ml of the solution was removed by theultrafiltration method. This ultrafiltration operation was repeated fivetimes and about 1.5% by weight of a blue solution of polystyrenesulfonic acid-doped poly(3,4-ethylenedioxythiophene) (PSS-PEDOT) wasobtained. It was taken as a π conjugated conductive polymer solution A.

Example 1

1.0 g of potassium hydroquinone sulfonate was added to 100 g of the πconjugated conductive polymer solution A obtained in Preparation Example3 and the mixture was uniformly dispersed to obtain a conductivecomposition solution.

The conductive polymer solution was uniformly coated on a glass anddried in an oven of 150° C. to form a coating film. Electriccharacteristics of the coating film were evaluated by the followingevaluation methods. The results are shown in Table 1.

TABLE 1 Retention rate of Rate of change of Electric electricconductivity electric conductivity conductivity depending on heatdepending on (S/cm) (%) humidity (%) Example 1 98 67.5 −3.2 Example 2 5653.5 11.3 Example 3 276 81.6 2.5 Example 4 132 86.4 −5.5 Example 5 65391.3 3.4 Example 6 283 89.5 3.3 Example 7 578 92.8 3.8 Example 8 45 45.45.4 Example 9 32 52.6 7.3 Example 10 420 88.2 3.4 Comparative 0.8 2.5−350 Example 1 Comparative 2.7 8.9 −490 Example 2 Comparative 5.8 10.3−487 Example 3 Comparative 4.5 0.8 −386 Example 4

(Evaluation Method)

Electric conductivity (S/cm): The electric conductivity of the coatingfilm was measured by a LORESTA (manufactured by Mitsubishi ChemicalCorporation).

The retention rate of electric conductivity depending on heat (%): Theelectric conductivity R_(25B) of the coating film at a temperature of25° C. was measured, the coating film after measurement was placed underan environment of 125° C. for 300 hours, then the coating film wasreturned to the temperature of 25° C. and the electric conductivityR_(25A) was measured. The retention rate of electric conductivitydepending on heat was calculated by the following formula. The retentionrate of electric conductivity depending on heat is an indicator of heatresistance.Retention rate of electric conductivity depending on heat (%)=100×R_(25A) /R _(25B)Rate of Change of Electric Conductivity Depending on Humidity (%):

The electric conductivity R_(25B) of the coating was measured at 25° C.and at a humidity of 60% RH. Then, the coating was allowed to stand at180° C. and 90% RH for 200 hours. The temperature of the coating wasreturned to 25° C. and 60% RH and the electric conductivity R_(25A) wasmeasured. The obtained values were applied to the following equation toobtain a rate of change of electric conductivity depending on humidity.The rate of change of electric conductivity depending on humidity is anindicator of moisture stability.Rate of change of electric conductivity depending on humidity (%)=100×(R₂₅ −R _(25A))/R _(25B)

Example 2

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that 0.48 g of hydroquinone was addedin place of potassium hydroquinone sulfonate in Example 1. The resultsare shown in Table 1.

Example 3

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that the amount of potassiumhydroquinone sulfonate added in Example 1 was changed from 1.0 g to 2.0g. The results are shown in Table 1.

Example 4

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that the amount of potassiumhydroquinone sulfonate added in Example 1 was changed from 1.0 g to 6.0g. The results are shown in Table 1.

Example 5

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that 1.5 g of 1,2,3-trihydroxybenzenewas added in place of potassium hydroquinone sulfonate in Example 1. Theresults are shown in Table 1.

Preparation Example 4

14.2 g of 3,4-ethylenedioxythiophene and a solution obtained bydissolving 38.8 g of poly(ethyl methacrylate sulfonic acid) in 2000 mlof ion-exchanged water were mixed at 20° C.

This mixed solution was maintained at 20° C., 29.64 g of ammoniumpersulfate dissolved in 200 ml of ion-exchanged water and 8.0 g of anoxidation catalyst solution of ferric sulfate were slowly added whilestirring, and then the mixture was stirred and reacted for 3 hours.

2000 ml of ion-exchanged water was added to the obtained solution, andabout 2000 ml of solution was removed by the ultrafiltration method.This operation was repeated three times.

200 ml of sulfuric acid diluted to 10% by weight and 2000 ml ofion-exchanged water were added to the obtained solution, about 2000 mlof the solution was removed by the ultrafiltration method, 2000 ml ofion-exchanged water was added to the residue, and about 2000 ml of thesolution was removed by the ultrafiltration method. The aboveultrafiltration operation was repeated three times.

Subsequently, 2000 ml of ion-exchanged water was added to the obtainedfiltrate and about 2000 ml of the solution was removed by theultrafiltration method. This ultrafiltration operation was repeated fivetimes and about 1.5% by weight of a blue solution of poly(ethylmethacrylate sulfonic acid)-doped poly(3,4-ethylenedioxythiophene)(PMAS-PEDOT) was obtained. It was taken as a π conjugated conductivepolymer solution B.

Example 6

2.0 g of potassium hydroquinone sulfonate which was dissolved in 5 ml ofwater beforehand was added to 100 g of the π conjugated conductivepolymer solution B obtained in Preparation Example 4 and the mixture wasuniformly dispersed to obtain a conductive composition solution.

The conductive polymer solution was uniformly coated on a glass anddried in an oven of 150° C. to form a coating film. Electriccharacteristics of the coating film were evaluated as in Example 1. Theresults are shown in Table 1.

Example 7

A coating film of the conductive composition was similarly obtained andevaluated as in Example 6 except that 1.5 g of 1,2,3-trihydroxybenzenewas added in place of potassium hydroquinone sulfonate in Example 6. Theresults are shown in Table 1.

Preparation Example 5

6.8 g of pyrrole and a solution obtained by dissolving 38.8 g ofpoly(ethyl methacrylate sulfonic acid) in 2000 ml of ion-exchanged waterwere mixed and cooled to 0° C.

This mixed solution was maintained at 0° C., 29.64 g of ammoniumpersulfate dissolved in 200 ml of ion-exchanged water and 8.0 g of anoxidation catalyst solution of ferric sulfate were slowly added whilestirring, and then the mixture was stirred for 3 hours.

2000 ml of ion-exchanged water was added to the obtained solution, andabout 2000 ml of solution was removed by the ultrafiltration method.This operation was repeated three times.

200 ml of sulfuric acid diluted to 10% by weight and 2000 ml ofion-exchanged water were added to the obtained solution, about 2000 mlof the solution was removed by the ultrafiltration method, 2000 ml ofion-exchanged water was added to the residue, and about 2000 ml of thesolution was removed by the ultrafiltration method. The aboveultrafiltration operation was repeated three times.

Subsequently, 2000 ml of ion-exchanged water was added to the obtainedfiltrate and about 2000 ml of the solution was removed by theultrafiltration method. This ultrafiltration operation was repeated fivetimes and about 1.5% by weight of a blue solution of poly(ethylmethacrylate sulfonic acid)-doped polypyrrole (PMAS-PPY) was obtained.It was taken as a π conjugated conductive polymer solution C.

Example 8

2.0 g of potassium hydroquinone sulfonate which was dissolved in 5 ml ofwater beforehand was added to 100 g of the π conjugated conductivepolymer solution C obtained in Preparation Example 5 and the mixture wasuniformly dispersed to obtain a conductive composition solution.

The conductive polymer solution was uniformly coated on a glass anddried in an oven of 150° C. to form a coating film. Electriccharacteristics of the coating film were evaluated as in Example 1. Theresults are shown in Table 1.

Example 9

A coating film of the conductive composition was similarly obtained andevaluated as in Example 8 except that 1.5 g of 1,2,3-trihydroxybenzenewas added in place of potassium hydroquinone sulfonate in Example 6. Theresults are shown in Table 1.

Example 10

1.5 g of 1,2,3-trihydroxybenzene was added to 100 g of the π conjugatedconductive polymer solution A obtained in Preparation Example 3.

Furthermore, 9 g of an aqueous polyester containing solid content of 25%by weight (brand name: PLAS COAT Z-448D, manufactured by Goo ChemicalCo., Ltd.) was added to the obtained solution and the mixture wasuniformly dispersed to obtain a conductive composition solution.

The conductive polymer solution was uniformly coated on a glass anddried in an oven of 150° C. to form a coating film. Electriccharacteristics of the coating film were evaluated as in Example 1. Theresults are shown in Table 1.

Comparative Example 1

6.8 g of pyrrole and a solution obtained by dissolving 10.8 g ofpolyacrylic acid in 1000 ml of ion-exchanged water were mixed and cooledto 0° C.

This mixed solution was maintained at 0° C., 29.64 g of ammoniumpersulfate dissolved in 200 ml of ion-exchanged water and 8.0 g of anoxidation catalyst solution of ferric sulfate were slowly added whilestirring, and then the mixture was stirred for 3 hours.

The obtained solution was controlled to pH 10 with 25% by weight ofaqueous ammonia, and then the solid content was precipitated withisopropyl alcohol and filtered. The filtrate was washed withion-exchanged water and this operation was repeated three times. Thefiltrate was redispersed in 1000 ml of ion-exchanged water to obtain apolyacrylic acid-polypyrrole colloidal solution.

The obtained polyacrylic acid-polypyrrole colloidal solution was coatedon a glass and dried in an oven of 150° C. to form a coating film.Electric characteristics of the coating film were evaluated as inExample 1. The results are shown in Table 1.

Comparative Examples 2 to 4

The π conjugated conductive polymer solution A obtained in PreparationExample 3 (Comparative Example 2), the π conjugated conductive polymersolution B obtained in Preparation Example 4 (Comparative Example 3),and the π conjugated conductive polymer solution C obtained inPreparation Example 5 (Comparative Example 4) were coated on a glass anddried in an oven of 150° C. to form coating films of the conductivecompositions. Electric characteristics of the coating films wereevaluated as in Example 1. The results are shown in Table 1.

The conductive compositions of Examples 1 to 10 each containing ahydroxy group-containing aromatic compound had high conductivity andalso had superior heat stability and moisture stability.

On the other hand, the conductive compositions of Comparative Examples 1to 4 each containing no hydroxy group-containing aromatic compound hadlow conductivity and also inferior heat stability and moisturestability.

Example 11

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that 3,4,5-methyl trihydroxybenzoate inthe amount shown in Table 2 in place of potassium hydroquinone sulfonatewas added to 100 g of the π conjugated conductive polymer solution Aobtained in Preparation Example 3. The results are shown in Table 2.

TABLE 2 Electric conductivity Addition amount (g) (S/cm) Example 11 0.1802 0.3 840 0.4 1011 0.5 764 0.7 868 1.0 800 1.3 642 Example 12 0.2 7800.3 795 0.5 721 0.6 741 0.8 627 1.2 780 1.5 428

Example 12

A coating film of the conductive composition was similarly obtained andevaluated as in Example 1 except that 3,4,5-propyl trihydroxybenzoate inthe amount shown in Table 2 in place of potassium hydroquinone sulfonatewas added to 100 g of the π conjugated conductive polymer solution Aobtained in Preparation Example 3. The results are shown in Table 2.

The conductive compositions of Examples 11 and 12 in which the hydroxygroup-containing aromatic compound was represented by the formula (1)had higher conductivity.

Example 13

A coating film obtained by adding 0.3 mol of 3,4,5-methyltrihydroxybenzoate in Example 11 had been left for 550 hours in an ovenof 150° C. The electric conductivity and retention rate of electricconductivity depending on heat of the heated coating film wereevaluated. The results are shown in Table 3.

Example 14

A coating film obtained in Example 5 had been left for 550 hours in anoven of 150° C. The electric conductivity and retention rate of electricconductivity depending on heat of the heated coating film wereevaluated. The results are shown in Table 3.

TABLE 3 Retention rate of electric Electric conductivity conductivitydepending on heat (S/cm) (%) Example 13 2259 84 Example 14 2423 61

The conductive compositions of Examples 13 and 14 containing the hydroxygroup-containing aromatic compound had high electric conductivity andretention rate of electric conductivity depending on heat. ComparativeExample 13 and Example 14, it was found that the conductive compositionof Example 13 in which the hydroxy group-containing aromatic compoundwas represented by the formula (1) had superior electric conductivityand higher retention rate of electric conductivity depending on heat.

Example 15

1.0 g of potassium hydroquinone sulfonate was added to 100 g of the πconjugated conductive polymer solution A obtained in Preparation Example3 and the mixture was uniformly dispersed to obtain an antistaticcoating material.

The obtained antistatic coating material was coated on a PET film having25 μm thickness with a comma coater and dried to form an antistaticcoating having about 0.1 μm thickness. Then, the surface resistancevalue of this antistatic coating was measured by a LORESTA (manufacturedby Mitsubishi Chemical Corporation). Moreover, the visible lighttransmittance (JIS Z 8701) and haze (JIS K 6714) were measured. Theresults are shown in Table 4.

TABLE 4 Surface resistance Visible light value (Ω) transmittance (%)Haze (%) Example 15 4 × 10³ 94.5 2.2 Example 16 5 × 10² 93.4 2.3 Example17 6 × 10³ 95.2 1.9 Example 18 3 × 10⁵ 95.8 1.6 Example 19 6 × 10³ 92.82.8 Example 20 3 × 10³ 93.7 2.4 Example 21 9 × 10³ 95.1 2.1 Example 22 6× 10⁵ 83.1 3.2 Example 23 2 × 10⁴ 84.4 3.0 Comparative 7 × 10⁵ 89.8 2.3Example 5 Comparative 5 × 10⁵ 87.5 2.7 Example 6 Comparative 3 × 10⁸82.9 2.9 Example 7

Example 16

An antistatic coating was similarly obtained and evaluated as in Example15 except that 1.5 g of 1,2,3-trihydroxybenzene in place of potassiumhydroquinone sulfonate of Example 15 was added to 100 g of the πconjugated conductive polymer solution A obtained in Preparation Example3. The results are shown in Table 4.

Example 17

An antistatic coating was similarly obtained and evaluated as in Example16 except that 10 g of an aqueous polyester solution of 25% by weight(brand name: PLAS COAT Z-561, manufactured by Goo Chemical Co., Ltd.)was further added to prepare an antistatic coating material. The resultsare shown in Table 4.

Example 18

An antistatic coating was similarly obtained and evaluated as in Example17 except that 3 g of allylmethacrylate and 5 g of urethane-basedacrylate (manufactured by Negami Chemical Industrial Co., Ltd.) wereadded in place of the aqueous polyester solution of Example 17 toprepare an antistatic coating material. The results are shown in Table4.

Example 19

2.0 g of potassium hydroquinone sulfonate aqueous solution which wasdissolved in 5 ml of water beforehand was added to 100 g of the πconjugated conductive polymer solution B obtained in Preparation Example4 and the mixture was uniformly dispersed to prepare an antistaticcoating material.

An antistatic coating was similarly obtained and evaluated as in Example15 from the obtained antistatic coating material. The results are shownin Table 4.

Example 20

An antistatic coating was similarly obtained and evaluated as in Example19 except that 1.5 g of 1,2,3-trihydroxybenzene in place of potassiumhydroquinone sulfonate was added to 100 g of the π conjugated conductivepolymer solution B obtained in Preparation Example 4. The results areshown in Table 4.

Example 21

An antistatic coating was similarly obtained and evaluated as in Example20 except that 10 g of an aqueous polyester solution of 25% by weight(brand name: PLAS COAT Z-561, manufactured by Goo Chemical Co., Ltd.)was further added to prepare an antistatic coating material. The resultsare shown in Table 4.

Example 22

1.5 g of 1,2,3-trihydroxybenzene was added to 100 g of the π conjugatedconductive polymer solution C obtained in Preparation Example 5 and themixture was uniformly dispersed to obtain an antistatic coatingmaterial. An antistatic coating was similarly obtained and evaluated asin Example 15 from the obtained antistatic coating material. The resultsare shown in Table 4.

Example 23

An antistatic coating material was similarly obtained as in Example 15except that 0.4 g of 3,4,5-methyltrihydroxybenzoate in place ofpotassium hydroquinone sulfonate was added to 100 g of the π conjugatedconductive polymer solution A obtained in Preparation Example 3 and 10 gof an aqueous polyester solution of 25% by weight (brand name: PLAS COATZ-561, manufactured by Goo Chemical Co., Ltd.) was further added. Anantistatic coating was similarly obtained and evaluated as in Example 15except that the obtained antistatic coating material was coated on a PETfilm having 200 μm thickness. The results are shown in Table 4.

Comparative Examples 5 to 7

The π conjugated conductive polymer solution A obtained in PreparationExample 3 (Comparative Example 5), the π conjugated conductive polymersolution B obtained in Preparation Example 4 (Comparative Example 6),and the π conjugated conductive polymer solution C obtained inPreparation Example 5 (Comparative Example 7) were coated on a glass anddried in an oven of 150° C. to form antistatic coatings. Electriccharacteristics of the antistatic coatings were evaluated as inExample 1. The results are shown in Table 4.

Antistatic coatings of Examples 15 to 23 each containing a hydroxygroup-containing aromatic compound had high conductivity and also hadsuperior heat stability and moisture stability. Especially, theantistatic coating of Example 23 in which the hydroxy group-containingaromatic compound was represented by the formula (1) had higherconductivity and stability.

On the other hand, antistatic coatings of Comparative Examples 5 to 7each containing no hydroxy group-containing aromatic compound had lowconductivity and also inferior heat stability and moisture stability.

Example 24

2.0 g of potassium hydroquinone sulfonate was added to 100 g of the πconjugated conductive polymer solution A and the mixture was uniformlydispersed to obtain a conductive polymer solution A′.

The obtained conductive polymer solution A′ was coated on a glass anddried in an oven of 120° C. to form a coating film. The electricconductivity of the obtained coating film was measured by a LORESTA(manufactured by Mitsubishi Chemical Corporation). The results are shownin Table 5.

TABLE 5 Electric ESR Electrostatic Conductivity (mΩ) capacity (μF)(S/cm) Initial 125° C., 500 hr Example 27 473 252 12 14 (Example 24)Example 28 469 634 8 10 (Example 25) Example 29 438 764 8 9 (Example 26)Example 30 563 252 9 10 (Example 24) Example 31 585 634 6 7 (Example 25)Comparative 484 2 57 795 Example 8

Example 25

A conductive polymer solution B′ was similarly obtained as in Example 24except that 1.5 of 1,2,3-trihydroxybenzene in place of potassiumhydroquinone sulfonate was added to 100 g of the π conjugated conductivepolymer solution A obtained in Preparation Example 3. The obtainedconductive polymer solution B′ was evaluated as in Example 24. Theresults are shown in Table 5.

Example 26

A conductive polymer solution C′ was similarly obtained as in Example 24except that 0.7 of 3,4,5-methyltrihydroxybenzoate in place of potassiumhydroquinone sulfonate was added to 100 g of the π conjugated conductivepolymer solution A obtained in preparation Example 3. The obtainedconductive polymer solution C′ was evaluated as in Example 24. Theresults are shown in Table 5.

Example 27

An anode lead terminal was connected to an etched aluminum foil (anodefoil), then chemically reacted (oxidized) in a 10% by weight aqueoussolution of ammonium adipate to form a dielectric layer at the aluminumsurface and give a capacitor intermediate.

Next, the capacitor intermediate product and an opposite aluminumcathode foil welded with a cathode lead terminal were laminated, and thelaminate was wound and taken as a capacitor element. At this time, aseparator was inserted between the anode foil and the cathode foil ofthe capacitor intermediate.

A capacitor element was dipped in the conductive polymer solution A′prepared in Example 24 and then dried with a hot-air dryer of 120° C. toform a solid electrolyte layer at the surface of capacitor intermediateproduct on the dielectric side.

Subsequently, the capacitor element with formed solid electrolyte layerand an electrolyte which was a solution of 20% by weight of ammoniumhydrogen adipate and 80% by weight of ethylene glycol were packed in analuminum case and sealed with a sealing gum to prepare a capacitor.

The electrostatic capacity at 120 Hz, the initial value of equivalentseries resistance (ESR) at 100 kHz and the ESR after 125° C. and 500hours of the prepared capacitor were measured by LCZ meter 2345(manufactured by NF Corporation). The results are shown in Table 5.

Example 28

A capacitor was similarly prepared and evaluated as in Example 27 exceptthat conductive polymer solution B′ was used in place of conductivepolymer solution A′. The results are shown in Table 5.

Example 29

A capacitor was similarly prepared and evaluated as in Example 27 exceptthat conductive polymer solution C′ was used in place of conductivepolymer solution A′. The results are shown in Table 5.

Example 30

An anode lead terminal was connected to an etched aluminum foil (anodefoil), then chemically reacted (oxidized) in a 10% by weight aqueoussolution of ammonium adipate to form a dielectric layer at the aluminumsurface and give a capacitor intermediate product.

Next, the capacitor intermediate was dipped in the conductive polymersolution A′ prepared in Example 24 and then dried with a hot-air dryerof 120° C. to form a solid electrolyte layer at the surface of capacitorintermediate product on the dielectric side.

Subsequently, a carbon paste was applied onto the formed solidelectrolyte layer and dried with a hot-air dryer of 120° C., and then asilver paste was further applied to form a conductive layer and driedwith a hot-air dryer of 120° C. to form a cathode.

A lead terminal was mounted to the cathode, then wound and taken as acapacitor element. At this time, a separator was inserted between theanode foil and the cathode foil of the capacitor intermediate product.

The capacitor element with formed solid electrolyte layer was packed inan aluminum case and sealed with a sealing gum to prepare a capacitor.

The electrostatic capacity at 120 Hz, the initial value of equivalentseries resistance (ESR) at 100 kHz and the ESR after 125° C. and 500hours of prepared capacitor were measured by LCZ meter 2345(manufactured by NF Corporation).

Example 31

A capacitor was similarly prepared and evaluated as in Example 30 exceptthat conductive polymer solution B′ was used in place of conductivepolymer solution A′. The results are shown in Table 5.

Comparative Example 8

A capacitor was similarly prepared and evaluated as in Example 27 exceptthat the π conjugated conductive polymer solution A obtained inPreparation Example 3 was used as a conductive polymer solution. Theresults are shown in Table 5.

In each capacitor of Examples 27 to 31 in which a solid electrolytelayer of a cathode comprised a π conjugated conductive polymer, apolyanion, and a hydroxy group-containing aromatic compound, the cathodehad excellent conductivity and low equivalent series resistance.Especially, the capacitor of Example 31 in which the hydroxygroup-containing aromatic compound was represented by the formula (1)had excellent conductivity and low equivalent series resistance in thecathode.

On the other hand, a capacitor of Comparative Example 8 in which a solidelectrolyte layer of a cathode comprised no hydroxy group-containingaromatic compound had low conductivity and high equivalent seriesresistance in the cathode.

Applications of the conductive composition of the present invention tovarious fields requiring the conductivity, such as conductive coating,antistatic agent, electromagnetic wave shielding agent, conductivematerial requiring transparency, battery material, capacitor material,conductive adhesive, sensor, electronic device material, semiconductormaterial, semiconductive material, electrostatic copying member,photosensitive member of printing, and the like, transfer body,intermediate point transfer body, conveying member, electrophotographicmaterial, and the like can be expected.

The antistatic coating material of the present invention enables toprepare an antistatic coating having high conductivity, flexibility andadhesion base at a low cost because the antistatic coating can be formedby a simple method such as coating, and the like and display sufficientantistatic property in a small amount.

The capacitor of the present invention has low equivalent seriesresistance (ESR) and can be manufactured by a simple method.

While preferred embodiments of the invention have been described andillustrated above, it should be understood that these are exemplary ofthe invention and are not to be considered as limiting. Additions,omissions, substitutions, and other modifications can be made withoutdeparting from the spirit or scope of the present invention.Accordingly, the invention is not to be considered as being limited bythe foregoing description, and is only limited by the scope of theappended claims.

1. A conductive composition comprising: a π conjugated conductivepolymer selected from the group consisting of polythiophene andpolypyrrole, a polyanion, a hydroxy group-containing aromatic compoundselected from the group consisting of 1,2,3-trihydroxybenzene and3,4,5-trihydroxybenzoate and a dopant.
 2. The conductive compositionaccording to claim 1, further comprising a binder resin.
 3. Theconductive composition according to claim 2, wherein the binder resin isleast one selected from the group consisting of polyurethane, polyester,acryl resin, polyamide, polyimide, epoxy resin, polyimide silicone, andmelamine resin.